ANTHROPIC_API_KEYAuthentication | — Documented | Primary API key for Claude API |
ANTHROPIC_AUTH_TOKENAuthentication | — Documented | Alternative bearer token; takes priority over API key |
ANTHROPIC_AWS_API_KEYCloud providers | — Documented | — |
ANTHROPIC_AWS_BASE_URLCloud providers | — Documented | — |
ANTHROPIC_AWS_WORKSPACE_IDCloud providers | — Documented | — |
ANTHROPIC_BASE_URLNetwork and proxy | — Documented | Custom endpoint for Anthropic services |
ANTHROPIC_BEDROCK_BASE_URLCloud providers | — Documented | Alternative Bedrock endpoint (alias) |
ANTHROPIC_BEDROCK_MANTLE_BASE_URLCloud providers | — Documented | — |
ANTHROPIC_BEDROCK_REGION_PREFIXCloud providers | — Documented | — |
ANTHROPIC_BEDROCK_SERVICE_TIERCloud providers | — Documented | — |
ANTHROPIC_BETASOther | — Documented | Comma-separated beta feature headers |
ANTHROPIC_CUSTOM_HEADERSOther | — Documented | Custom HTTP headers (newline-separated Key: Value) |
ANTHROPIC_CUSTOM_MODEL_OPTIONModels and thinking | — Documented | — |
ANTHROPIC_CUSTOM_MODEL_OPTION_DESCRIPTIONModels and thinking | — Documented | — |
ANTHROPIC_CUSTOM_MODEL_OPTION_NAMEModels and thinking | — Documented | — |
ANTHROPIC_CUSTOM_MODEL_OPTION_SUPPORTED_CAPABILITIESModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_FABLE_MODELModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_FABLE_MODEL_DESCRIPTIONModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_FABLE_MODEL_NAMEModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_FABLE_MODEL_SUPPORTED_CAPABILITIESModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_HAIKU_MODELModels and thinking | — Documented | Override Haiku model ID |
ANTHROPIC_DEFAULT_HAIKU_MODEL_DESCRIPTIONModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_HAIKU_MODEL_NAMEModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_HAIKU_MODEL_SUPPORTED_CAPABILITIESModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_MODELModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_OPUS_MODELModels and thinking | — Documented | Override Opus model ID |
ANTHROPIC_DEFAULT_OPUS_MODEL_DESCRIPTIONModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_OPUS_MODEL_NAMEModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_OPUS_MODEL_SUPPORTED_CAPABILITIESModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_SONNET_MODELModels and thinking | — Documented | Override Sonnet model ID |
ANTHROPIC_DEFAULT_SONNET_MODEL_DESCRIPTIONModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_SONNET_MODEL_NAMEModels and thinking | — Documented | — |
ANTHROPIC_DEFAULT_SONNET_MODEL_SUPPORTED_CAPABILITIESModels and thinking | — Documented | — |
ANTHROPIC_FEDERATION_RULE_IDOther | — Documented | — |
ANTHROPIC_FOUNDRY_API_KEYCloud providers | — Documented | Foundry API key |
ANTHROPIC_FOUNDRY_AUTH_TOKENCloud providers | — Documented | — |
ANTHROPIC_FOUNDRY_BASE_URLCloud providers | — Documented | Custom Foundry endpoint |
ANTHROPIC_FOUNDRY_RESOURCECloud providers | — Documented | Foundry resource name |
ANTHROPIC_LOGDebugging | — | SDK internal logging level |
ANTHROPIC_MODELModels and thinking | — Documented | Override the default Claude model |
ANTHROPIC_ORGANIZATION_IDOther | — Documented | — |
ANTHROPIC_PROFILEDebugging | — Documented | — |
ANTHROPIC_SMALL_FAST_MODELModels and thinking | — Documented | Override small/fast model for quick operations |
ANTHROPIC_SMALL_FAST_MODEL_AWS_REGIONCloud providers | — Documented | AWS region for small fast model on Bedrock |
ANTHROPIC_VERTEX_BASE_URLCloud providers | — Documented | — |
ANTHROPIC_VERTEX_PROJECT_IDCloud providers | — Documented | Google Cloud project ID |
ANTHROPIC_WORKSPACE_IDOther | — Documented | — |
API_FORCE_IDLE_TIMEOUTNetwork and proxy | — Documented | — |
API_TIMEOUT_MSNetwork and proxy | — Documented | Request timeout in milliseconds |
AWS_BEARER_TOKEN_BEDROCKCloud providers | — Documented | Bearer token for Bedrock authentication |
BASH_DEFAULT_TIMEOUT_MSNetwork and proxy | — Documented | — |
BASH_MAX_OUTPUT_LENGTHShell and tools | — Documented | Max bash output character length |
BASH_MAX_TIMEOUT_MSNetwork and proxy | — Documented | — |
BETA_TRACING_ENDPOINTOther | — Documented | Custom endpoint for beta tracing |
CCR_FORCE_BUNDLEFeature toggles | — Documented | — |
CLAUDECODEOther | — Documented | Set to 1 in child shell processes (auto-set) |
CLAUDE_AFK_COUNTDOWN_MSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_AFK_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_AFTER_LAST_COMPACTContext and compaction | Present since v2.1.69 or earlier | Request only conversation logs after last compaction |
CLAUDE_AGENTAgents and subagents | Removed in v2.1.310 | Short-form identifier for the current agent, used in inter-agent messaging and log attribution. |
CLAUDE_AGENTS_AUTO_RELAUNCHED_ATAgents and subagents | Added between v2.1.118 and v2.1.123 | Timestamp set when the agent fleet was automatically relaunched after a crash. Downstream consumers can detect state that predates the relaunch and invalidate… |
CLAUDE_AGENTS_SELECTAgents and subagents | Added between v2.1.118 and v2.1.123 | Selects which agents from a fleet configuration are active for this session or job. Analogous to a feature flag for agents: target a specific agent variant… |
CLAUDE_AGENT_SDK_CLIENT_APPAgents and subagents | Present since v2.1.69 or earlier | Client application name |
CLAUDE_AGENT_SDK_DISABLE_BUILTIN_AGENTSAgents and subagents | Present since v2.1.69 or earlier Documented | Disable built-in agent types |
CLAUDE_AGENT_SDK_DISABLE_MCP_MANIFESTSAgents and subagents | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_AGENT_SDK_MCP_NO_PREFIXAgents and subagents | Present since v2.1.69 or earlier Documented | Don't prefix MCP tool names with server name |
CLAUDE_AGENT_SDK_VERSIONAgents and subagents | Present since v2.1.69 or earlier | Agent SDK version sent in User-Agent header |
CLAUDE_AI_AUTHORIZE_URLAuthentication | Present since v2.1.69 or earlier | Authorization URL endpoint |
CLAUDE_AI_HOSTOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_AI_IMPORT_SHAPEOther | Removed between v2.1.252 and v2.1.266 | — |
CLAUDE_AI_INFERENCE_SCOPEOther | Present since v2.1.69 or earlier | — |
CLAUDE_AI_OAUTH_SCOPESAuthentication | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_AI_ORIGINOther | Added in v2.1.84 | Overrides the base URL for Claude AI authentication endpoints. This complements the existing CLAUDE_CODE_API_BASE_URL (which controls the inference endpoint)… |
CLAUDE_AI_PLUGINS_SCOPEPlugins and skills | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_AI_PROFILE_SCOPEDebugging | Present since v2.1.69 or earlier | — |
CLAUDE_AI_PROJECTS_READ_SCOPEOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_AI_PROJECTS_WRITE_SCOPEOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_AI_SESSIONS_SCOPESessions | Added in v2.1.300 | — |
CLAUDE_API_SKILL_DESCRIPTIONPlugins and skills | Removed between v2.1.247 and v2.1.252 | Registration hook for the built-in "claude-api" skill that bundles Anthropic SDK docs (Python, TypeScript, Java, Go, Ruby, PHP, C#, curl) plus shared… |
CLAUDE_ARTIFACT_HOST_GRANTOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_ASYNC_AGENT_STALL_TIMEOUT_MSNetwork and proxy | Added between v2.1.108 and v2.1.114 Documented | Default 600,000ms (10 minutes). Directly backs v2.1.113's "subagents that stall mid-stream now fail with a clear error after 10 minutes" changelog bullet. Tune… |
CLAUDE_AUTOCOMPACT_PCT_OVERRIDEContext and compaction | Present since v2.1.69 or earlier Documented | Set when auto-compaction triggers (percentage threshold) |
CLAUDE_AUTO_BACKGROUND_TASKSSessions | Removed in v2.1.310 Documented | Enable automatic background task execution |
CLAUDE_AX_ANNOUNCEMENT_HOLD_MSTerminal and UI | Added in v2.1.288 | — |
CLAUDE_AX_PREPARK_MSTerminal and UI | Removed in v2.1.310 Documented | — |
CLAUDE_AX_REWRITE_HELD_ANNOUNCEMENTTerminal and UI | Added in v2.1.288 | — |
CLAUDE_AX_SCREEN_READERTerminal and UI | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_AX_STARTUP_QUIET_MSTerminal and UI | Added between v2.1.215 and v2.1.217 Documented | Startup quiet window (milliseconds) for screen-reader mode. First shipped v2.1.217; the changelog names the fix but not the knob. |
CLAUDE_BASEOther | Added in v2.1.92 | Likely overrides the base URL or base configuration path for Claude Code. This is a compact alternative to the more specific CLAUDE_CODE_API_BASE_URL —… |
CLAUDE_BASH_MAINTAIN_PROJECT_WORKING_DIRShell and tools | Present since v2.1.69 or earlier Documented | Maintain consistent working directory across commands |
CLAUDE_BASH_NO_LOGINShell and tools | — | Replaced by CLAUDE_CODE_SHELL_PREFIX |
CLAUDE_BG_AUTH_SNAPSHOT_PATHAuthentication | Added between v2.1.138 and v2.1.143 | Path for snapshotting background session auth credentials to disk. Fixes the failure mode where a background session lost auth mid-run and corrupted its state… |
CLAUDE_BG_AUTO_MEMORY_OFFMemory and CLAUDE.md | Added in v2.1.285 | — |
CLAUDE_BG_BACKENDSessions | Added between v2.1.108 and v2.1.114 | Set to "daemon" to route background work through a daemon backend. The code path is wrapped around EIO/EPIPE handling — pipe/socket IPC with graceful… |
CLAUDE_BG_CARRIED_PROMPTS_SHA256Sessions | Added in v2.1.295 | — |
CLAUDE_BG_CLAIM_AUTHAuthentication | Removed in v2.1.310 | — |
CLAUDE_BG_DISPATCHER_RATE_LIMIT_TIERSessions | Removed in v2.1.310 | — |
CLAUDE_BG_DISPATCHER_SUBSCRIPTION_TYPESessions | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_BG_GATEWAY_WITHHELDSessions | Added between v2.1.301 and v2.1.303 | Carries the path of an LLM gateway that was set in your shell but not passed through to a background session opened from another folder. It backs the clearer… |
CLAUDE_BG_ISOLATIONSessions | Added between v2.1.118 and v2.1.123 | Isolation mode for background agent processes — controls how separated the daemon's process space is from the foreground session. Values likely span a… |
CLAUDE_BG_MEMORY_TOGGLED_OFFMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BG_POST_CLEAR_RESPAWNSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BG_PTY_AUTHAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BG_RENDEZVOUS_SOCKSessions | Added between v2.1.118 and v2.1.123 | Socket path for the IPC channel between a foreground Claude session and the background daemon. The daemon starts independently and listens; the foreground… |
CLAUDE_BG_RV_AUTHAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BG_SESSION_PERMISSION_RULESPermissions and sandbox | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BG_SOCKET_TOKENS_PATHAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BG_SOURCESessions | Added between v2.1.118 and v2.1.123 | Tags where a background job originated: CLI, SDK, Remote Control, another agent. Present on the daemon side so it can route, prioritize, or attribute work… |
CLAUDE_BG_STARTUP_WEDGE_MSSessions | Added between v2.1.128 and v2.1.138 | Startup jitter for background sessions. When you spawn many agents simultaneously, they can race for the same auth or daemon connections. This introduces a… |
CLAUDE_BG_TCC_DISCLAIMEDSessions | Added between v2.1.138 and v2.1.143 | macOS TCC (Transparency, Consent, and Control) permission disclaimer state for background sessions. Background agents without a controlling terminal need… |
CLAUDE_BG_WORKSPACE_TRUSTEDSessions | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_BRIDGE_BASE_URLNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BRIDGE_OAUTH_TOKENAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BRIDGE_REATTACH_GROUPINGSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BRIDGE_REATTACH_NO_BACKFILLSessions | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_BRIDGE_REATTACH_OUTBOUND_ONLYSessions | Removed in v2.1.305 | — |
CLAUDE_BRIDGE_REATTACH_OWNER_ACCTSessions | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_BRIDGE_REATTACH_OWNER_ORGSessions | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_BRIDGE_REATTACH_SEQSessions | Added in v2.1.118 | Sequence number for the bridge reconnection protocol. At-least-once delivery semantics: the daemon replays events the bridge missed since this sequence point.… |
CLAUDE_BRIDGE_REATTACH_SESSIONSessions | Added in v2.1.118 | Session identity used during bridge reconnection. Pairs with CLAUDE_BRIDGE_REATTACH_SEQ — the bridge presents both to resume exactly where it disconnected. |
CLAUDE_BRIDGE_SESSION_INGRESS_URLNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_BRIDGE_USE_CCR_V2Sessions | Removed between v2.1.143 and v2.1.212 | Toggle for CCR v2 bridge protocol — companion to the existing CLAUDE_CODE_USE_CCR_V2 introduced in v2.1.69. Suggests the bridge layer (IDE extensions, remote… |
CLAUDE_BYTE_STREAM_IDLE_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CHROME_CLASSIFIER_FLOOROther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CHROME_PAIRED_DEVICE_IDOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CHROME_PERMISSION_MODEPermissions and sandbox | Present since v2.1.69 or earlier | Permission mode for Claude for Chrome |
CLAUDE_CHROME_TAB_GROUP_KEYOther | Added in v2.1.286 | — |
CLAUDE_CLIENT_PRESENCE_FILEOther | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_3P_PROBE_WROTE_OPUS_DEFAULTModels and thinking | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_3P_PROBE_WROTE_SONNET_DEFAULTModels and thinking | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_3P_SEEDED_OPUS_DEFAULTModels and thinking | Added in v2.1.285 | — |
CLAUDE_CODE_3P_SEEDED_SONNET_DEFAULTModels and thinking | Added in v2.1.310 | — |
CLAUDE_CODE_ACCESSIBILITYTerminal and UI | Present since v2.1.69 or earlier Documented | Enable accessibility mode; disables cursor hiding |
CLAUDE_CODE_ACCOUNT_TAGGED_IDOther | Added between v2.1.77 and v2.1.79 | Stores a tagged or decorated account identifier, distinct from the existing CLAUDE_CODE_ACCOUNT_UUID. While the UUID is a raw unique identifier, a "tagged" ID… |
CLAUDE_CODE_ACCOUNT_UUIDOther | Removed in v2.1.310 | Pre-configured account UUID |
CLAUDE_CODE_ACCOUNT_UUIDIOther | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_ACTIONOther | Present since v2.1.69 or earlier | Indicates running as GitHub Action |
CLAUDE_CODE_ACT_DONT_REDERIVEOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ADDITIONAL_DIRECTORIES_CLAUDE_MDMemory and CLAUDE.md | Removed between v2.1.307 and v2.1.309 Documented | Additional directories to scan for CLAUDE.md files (colon-separated) |
CLAUDE_CODE_ADDITIONAL_PROTECTIONOther | Present since v2.1.69 or earlier | Add additional protection header to API requests |
CLAUDE_CODE_ADOPT_UNDERIVABLE_PARKED_PERMISSIONPermissions and sandbox | Removed in v2.1.307 | — |
CLAUDE_CODE_AGENTAgents and subagents | Added between v2.1.118 and v2.1.123 | Full agent descriptor passed into a spawned agent process — likely the agent's frontmatter (tools, allowed/disallowed lists, system prompt path) so the child… |
CLAUDE_CODE_AGENT_COST_STEERAgents and subagents | Removed between v2.1.138 and v2.1.143 | Controls cost-aware behavior for subagent delegation. As Claude Code's multi-agent architecture matures — named subagents now appear in @ mention typeahead[1]… |
CLAUDE_CODE_AGENT_LIST_IN_MESSAGESAgents and subagents | Removed between v2.1.143 and v2.1.212 | An early agent-listing toggle, made obsolete by the Agent View and coordinator surfaces that now own how agents are shown. |
CLAUDE_CODE_AGENT_PROGRESS_SUMMARIESAgents and subagents | Added in v2.1.310 | — |
CLAUDE_CODE_AGENT_PROXY_GH_SHIMNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_AGENT_PROXY_GIT_CONFIGNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_AGENT_PROXY_GIT_HOSTSNetwork and proxy | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_AGENT_RULE_DISABLEDAgents and subagents | Present since v2.1.69 or earlier | Disable agent rules |
CLAUDE_CODE_AGENT_SWARMSAgents and subagents | — | Replaced by CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS |
CLAUDE_CODE_AGENT_VIEW_RELAUNCHAgents and subagents | Added between v2.1.138 and v2.1.143 | Force-relaunches the Agent View UI component when it gets into a bad state. The Agent View is a separate surface from the main session; this is its dedicated… |
CLAUDE_CODE_ALDER_WICKETOther | Removed in v2.1.218 | — |
CLAUDE_CODE_ALLOW_OTHER_MODELSModels and thinking | Added between v2.1.301 and v2.1.303 | Set to 1 to start on a model that the --client-data-url document has no entry for, without applying its per-model client data, instead of exiting. Same as… |
CLAUDE_CODE_ALTGR_AS_TEXTOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ALT_SCREEN_FULL_REPAINTTerminal and UI | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_ALWAYS_ENABLE_EFFORTModels and thinking | Added in v2.1.70 Documented | Force-enable reasoning effort level regardless of other settings. Useful for ensuring CLAUDE_CODE_EFFORT_LEVEL always takes effect, even in contexts where it… |
CLAUDE_CODE_AMBER_ASTROLABEOther | Added between v2.1.215 and v2.1.217 | — |
CLAUDE_CODE_API_BASE_URLNetwork and proxy | Removed in v2.1.310 | Custom Claude Code API base URL for proxies |
CLAUDE_CODE_API_KEY_FILE_DESCRIPTORAuthentication | Present since v2.1.69 or earlier | File descriptor to read API key from |
CLAUDE_CODE_API_KEY_HELPER_TTL_MSAuthentication | Present since v2.1.69 or earlier Documented | Cache TTL for API key helper |
CLAUDE_CODE_APPEND_PROMPT_HEADOther | Added in v2.1.284 | — |
CLAUDE_CODE_ARG_KEY_SHAPEOther | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_ARTIFACTOther | Removed in v2.1.310 | Turns on Artifacts, with companions for its API endpoint, direct upload, and MCP exposure. Claude Code can produce a first-class artifact now — and share it… |
CLAUDE_CODE_ARTIFACTS_API_BASE_URLNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ARTIFACTS_API_TOKENAuthentication | Added between v2.1.219 and v2.1.221 | — |
CLAUDE_CODE_ARTIFACT_ASK_FIRSTOther | Added in v2.1.310 | — |
CLAUDE_CODE_ARTIFACT_ASSETSOther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_ARTIFACT_ASSET_BASE_URLNetwork and proxy | Added between v2.1.219 and v2.1.221 | — |
CLAUDE_CODE_ARTIFACT_AUTO_OPENOther | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_ARTIFACT_COMMENTSOther | Added between v2.1.219 and v2.1.221 Documented | — |
CLAUDE_CODE_ARTIFACT_COMMENTS_AUTOREACTOther | Added between v2.1.219 and v2.1.221 Documented | — |
CLAUDE_CODE_ARTIFACT_COMMENT_FAST_ACKOther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_ARTIFACT_COMMENT_FAST_ACK_FIXEDOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_ARTIFACT_COMMENT_RESPONDEROther | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_CODE_ARTIFACT_DBOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_CODE_ARTIFACT_DB_STR_REPLACEOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_ARTIFACT_DELETEOther | Added between v2.1.238 and v2.1.241 | Enables the delete-Artifact path (owner-only, requires confirmation, blocked in plan mode). The gate refuses in remote sessions and otherwise falls back to the… |
CLAUDE_CODE_ARTIFACT_DIRECT_UPLOADOther | Removed between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_ARTIFACT_FDOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_FIVE_CLASS_ASKSOther | Removed in v2.1.293 | — |
CLAUDE_CODE_ARTIFACT_FRESH_READOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_HOTOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_ARTIFACT_INHERITED_TYPE_GRANTOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_LIVE_BASE_URLNetwork and proxy | Added between v2.1.219 and v2.1.221 | — |
CLAUDE_CODE_ARTIFACT_MCPMCP | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ARTIFACT_MULTI_FILEOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_ARTIFACT_OPENING_PREFETCHOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_OPEN_ACTIONOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_ARTIFACT_PATH_PINOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_PINOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_ARTIFACT_PRESENCEOther | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_ARTIFACT_PREVIEWOther | Removed in v2.1.310 | — |
CLAUDE_CODE_ARTIFACT_PREVIEW_EMULATOROther | Added in v2.1.292 | Pins the artifact-preview emulator on (true) or off (false); left unset, a feature flag decides. When on, the emulator checks its skill's files first and stays… |
CLAUDE_CODE_ARTIFACT_PUBLISH_EDITSOther | Added in v2.1.299 Documented | — |
CLAUDE_CODE_ARTIFACT_QUICKSTARTOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_REPLOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_ARTIFACT_ROOMOther | Added in v2.1.238 | — |
CLAUDE_CODE_ARTIFACT_SHAREOther | Added in v2.1.286 | — |
CLAUDE_CODE_ARTIFACT_SHARE_PROBE_REUSE_MSOther | Added between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_ARTIFACT_START_KITOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_ARTIFACT_SYNC_BASE_URLNetwork and proxy | Added in v2.1.238 | — |
CLAUDE_CODE_ARTIFACT_TEXT_VARIANTOther | Removed in v2.1.296 | — |
CLAUDE_CODE_ARTIFACT_TOOLSETShell and tools | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_ARTIFACT_TYPESOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_ARTIFACT_TYPE_CATALOGDebugging | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_ARTIFACT_TYPE_CLOUD_CREATEOther | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_ARTIFACT_VERIFYOther | Added in v2.1.238 | — |
CLAUDE_CODE_ARTIFACT_VERSIONSOther | Added in v2.1.292 | When set, the session can list and read an artifact's earlier versions; without it, a session reports that an artifact's earlier versions are not available.… |
CLAUDE_CODE_ARTIFACT_VIEWER_BASE_URLNetwork and proxy | Added in v2.1.229 | — |
CLAUDE_CODE_ATTACHMENTS_BY_PATHOther | Added in v2.1.300 | When set, the attachment handler takes the by-path route instead of an upload mode, so attachments are referenced by their file path rather than having their… |
CLAUDE_CODE_ATTACHMENTS_IN_USER_DATAOther | — | Off unless set. In remote sessions it governs reading session attachments from a user-data uploads root, behind a retention check that withholds the path when… |
CLAUDE_CODE_ATTRIBUTION_ANNOUNCEMENTOther | Removed in v2.1.310 | — |
CLAUDE_CODE_ATTRIBUTION_HEADEROther | Present since v2.1.69 or earlier Documented | API billing header in system prompt |
CLAUDE_CODE_ATTRIBUTION_PROJECTOther | Added in v2.1.304 | — |
CLAUDE_CODE_ATTRIBUTION_STATUS_TIMEOUT_MSNetwork and proxy | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_AUTH_FAIL_EXIT_MSAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_AUTOUPDATER_DISABLED_BY_HOSTOther | Added in v2.1.295 | — |
CLAUDE_CODE_AUTO_BACKGROUND_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_AUTO_BACKGROUND_WORKER_CHECKIN_SECONDSSessions | Removed between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_AUTO_COMPACT_WINDOWContext and compaction | Added between v2.1.77 and v2.1.79 Documented | Controls the token window threshold at which automatic context compaction kicks in. Works alongside the existing CLAUDE_AUTOCOMPACT_PCT_OVERRIDE variable but… |
CLAUDE_CODE_AUTO_CONNECT_IDENetwork and proxy | Present since v2.1.69 or earlier Documented | Auto-connect to IDE on startup |
CLAUDE_CODE_AUTO_MODE_ARTIFACT_CONSENT_RULEPermissions and sandbox | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_AUTO_MODE_CANDIDATE_WORDINGPermissions and sandbox | Removed in v2.1.286 | — |
CLAUDE_CODE_AUTO_MODE_CLASSIFIER_OVERLAPPermissions and sandbox | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_AUTO_MODE_CLASSIFIER_QUEUEPermissions and sandbox | Removed between v2.1.219 and v2.1.221 | — |
CLAUDE_CODE_AUTO_MODE_CLASSIFY_ASK_USER_QUESTIONPermissions and sandbox | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_CODE_AUTO_MODE_CLASSIFY_EDITSPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Turns the classification pass on: every edit runs through the classifier before it touches disk. Every change leaves a recorded decision you can inspect, which… |
CLAUDE_CODE_AUTO_MODE_COMPACT_THREAD_RULEContext and compaction | Added in v2.1.299 | — |
CLAUDE_CODE_AUTO_MODE_EDIT_REMOVALPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Governs whether Auto mode may delete content as part of an edit. Deletions are the riskiest edit class, so they get their own policy. |
CLAUDE_CODE_AUTO_MODE_EDIT_REMOVAL_CAPPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Caps how much a single autonomous edit can remove before it's held for a human. A direct answer to the runaway-refactor failure where an agent "simplifies" by… |
CLAUDE_CODE_AUTO_MODE_EMAIL_SENDER_REPLY_TURNPermissions and sandbox | Added in v2.1.305 | — |
CLAUDE_CODE_AUTO_MODE_EMAIL_SENDER_TURNPermissions and sandbox | Added in v2.1.305 | — |
CLAUDE_CODE_AUTO_MODE_EXTERNAL_PERMISSIONSPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Hands permission decisions to an external policy engine instead of the built-in prompt. This is the hook an enterprise needs to enforce its own approval rules… |
CLAUDE_CODE_AUTO_MODE_GIT_STATUSPermissions and sandbox | Removed in v2.1.310 | Feeds the working tree's git status into the classifier's context. An edit means something different in a clean repo than in one with forty dirty files. |
CLAUDE_CODE_AUTO_MODE_GIT_STATUS_LIMITPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Bounds how much of that status is included, so the classifier prompt doesn't balloon in large or messy repos. Cost and latency control for the gate. |
CLAUDE_CODE_AUTO_MODE_GIT_STATUS_UPLOADSPermissions and sandbox | Removed in v2.1.310 | Controls whether git-status context is uploaded to the classification service. A data-governance knob — some orgs don't want file paths and change sets leaving… |
CLAUDE_CODE_AUTO_MODE_HEARTH_MEMBER_RELAY_ROWSPermissions and sandbox | Added in v2.1.286 | — |
CLAUDE_CODE_AUTO_MODE_MODELModels and thinking | Added between v2.1.143 and v2.1.212 Documented | Picks the model that classifies each proposed edit — deliberately separate from the model doing the work. A small, fast model here keeps the safety check cheap… |
CLAUDE_CODE_AUTO_MODE_OUTCOME_CODESPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Structured outcome codes for the classifier's verdicts instead of free text. Makes autonomous-edit outcomes machine-readable — the basis for telemetry,… |
CLAUDE_CODE_AUTO_MODE_PRIOR_ASSISTANT_CONTEXTContext and compaction | Added between v2.1.143 and v2.1.212 | Feeds prior assistant turns into the decision, so the classifier can see the reasoning behind an edit. Intent matters — the same diff can be safe or reckless… |
CLAUDE_CODE_AUTO_MODE_REMOTE_BROWSERPermissions and sandbox | Added in v2.1.304 | — |
CLAUDE_CODE_AUTO_MODE_REPO_VISIBILITYPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Lets behavior depend on whether the repo is public or private. Being more conservative in public repos, where a bad edit is instantly visible, is the obvious… |
CLAUDE_CODE_AUTO_MODE_SEGMENTED_TRANSCRIPTPermissions and sandbox | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_AUTO_MODE_SERVERPermissions and sandbox | Added in v2.1.310 Documented | — |
CLAUDE_CODE_AUTO_MODE_SIBLING_CONTEXTContext and compaction | Removed between v2.1.219 and v2.1.221 | Includes sibling files (or sessions) when classifying. Lets the gate reason about consistency across related files instead of judging each change in isolation. |
CLAUDE_CODE_AUTO_MODE_TEMPERATUREPermissions and sandbox | Added between v2.1.143 and v2.1.212 | Temperature for the classifier. Low values make the safe/hold call deterministic and repeatable — exactly what you want for a gate that fires on every write. |
CLAUDE_CODE_AUTO_MODE_THREAD_ASK_HELDPermissions and sandbox | Added in v2.1.307 | — |
CLAUDE_CODE_AUTO_MODE_TIERPermissions and sandbox | Added in v2.1.286 | — |
CLAUDE_CODE_AWS_CHAIN_RESOLVE_TIMEOUT_MSCloud providers | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_BASALT_COVEOther | Added between v2.1.143 and v2.1.212 | An internal codename — one of five this stretch (PEWTER_OWL, LANTERN_PRISM, WALNUT_SPIRE, and a PEWTER_OWL_TOOL). Named flags with no changelog entry are… |
CLAUDE_CODE_BASE_REFOther | Present since v2.1.69 or earlier | Git base ref for diff operations |
CLAUDE_CODE_BASE_REFSOther | — | Specifies base git references (branches, tags, or SHAs) for diff comparison when Claude Code operates in a worktree or feature branch. In multi-worktree agent… |
CLAUDE_CODE_BASH_EDIT_DIFFShell and tools | Added between v2.1.266 and v2.1.269 Documented | — |
CLAUDE_CODE_BASH_OUTPUT_AUDIENCE_NOTEShell and tools | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_BASH_SANDBOX_SHOW_INDICATORPermissions and sandbox | Present since v2.1.69 or earlier | Show indicator when bash runs in sandbox |
CLAUDE_CODE_BENCH_LIVE_COUNTSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_BG_CLASSIFIER_MODELModels and thinking | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_BG_TASKS_REPORT_RUNNINGSessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_BISON_CAIRNOther | Added between v2.1.215 and v2.1.217 | — |
CLAUDE_CODE_BLOCKING_LIMIT_OVERRIDETerminal and UI | Present since v2.1.69 or earlier | Override token limit for input blocking |
CLAUDE_CODE_BREEZY_HORIZONOther | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_BRIDGE_CHILD_ARTIFACTSessions | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_BRIDGE_CHILD_AUTO_DEFAULTSessions | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_BRIDGE_CHILD_MACHINE_SETTINGSSessions | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_BRIDGE_CHILD_PROJECTS_ENTRYPOINTSessions | Added in v2.1.310 | — |
CLAUDE_CODE_BRIDGE_MCP_CARRIERMCP | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_BRIDGE_OWNER_ACCOUNT_UUIDSessions | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_BRIDGE_OWNER_ORG_UUIDSessions | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_BRIDGE_PROMPT_SHA256Sessions | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_BRIDGE_SESSION_IDSessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_BRIDGE_SOURCE_DIRSessions | Added in v2.1.286 | — |
CLAUDE_CODE_BRIEFOther | Added between v2.1.70 and v2.1.72 | Toggle brief/concise output mode — shorter responses from Claude. Useful for scripted workflows or agents that don't need verbose explanations. |
CLAUDE_CODE_BRIEF_UPLOADOther | Removed in v2.1.310 | Brief mode specifically for upload operations. Likely suppresses progress details when uploading files or context to the session. |
CLAUDE_CODE_BS_AS_CTRL_BACKSPACEOther | Added between v2.1.108 and v2.1.114 Documented | Treats a bare backspace keypress as Ctrl+Backspace (delete-word). Default: on Windows unless the terminal is mintty or cygwin. Exists because Windows terminals… |
CLAUDE_CODE_BUBBLEWRAPPermissions and sandbox | Present since v2.1.69 or earlier | Set to 1 when running in bubblewrap sandbox (Linux) [6] |
CLAUDE_CODE_BYOC_ENABLE_DATADOGTelemetry | Added between v2.1.128 and v2.1.138 | Opt-in Datadog telemetry for BYOC (Bring Your Own Cloud) Bedrock/Vertex deployments. Route Claude Code operational metrics to Datadog alongside your existing… |
CLAUDE_CODE_CALM_MOCHIOther | Added in v2.1.290 | — |
CLAUDE_CODE_CARVED_SLATEOther | Removed between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_CCR_EARLY_HYDRATE_PREFETCHOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_CCR_EARLY_PLUGINS_SYNCPlugins and skills | Added in v2.1.286 | — |
CLAUDE_CODE_CCR_EARLY_REMOTE_CONNECTNetwork and proxy | Removed in v2.1.310 | — |
CLAUDE_CODE_CCR_EARLY_SKILLS_SYNCPlugins and skills | Added in v2.1.287 | — |
CLAUDE_CODE_CCR_EARLY_SYNC_AFTER_SETTINGS_REFUSALOther | Added in v2.1.305 | — |
CLAUDE_CODE_CCR_EVENT_FLUSH_POLICYOther | Added in v2.1.305 | — |
CLAUDE_CODE_CCR_FOLD_FIRST_TURN_RESCANOther | Added in v2.1.287 | — |
CLAUDE_CODE_CCR_LAZY_SUBAGENT_HYDRATEAgents and subagents | Removed between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_CCR_OWN_CONNECTION_POOLNetwork and proxy | Added between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_CCR_SKIP_FRESH_MIGRATIONSFeature toggles | Added in v2.1.287 | — |
CLAUDE_CODE_CCR_SURFACEOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_CCR_WORKER_SOCKETOther | Added in v2.1.299 | — |
CLAUDE_CODE_CERT_STOREAuthentication | Added between v2.1.100 and v2.1.104 Documented | Comma-separated CA sources to trust: bundled, system, or both (the default since v2.1.101). Unknown values are ignored with a warning. |
CLAUDE_CODE_CHILD_SESSIONSessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_CHROME_MCP_ORG_DENIEDMCP | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_CLASSIFIER_SUMMARYOther | Added between v2.1.118 and v2.1.123 | Carries the output of a prompt classifier as a structured summary. Where CLAUDE_CODE_VERIFY_PROMPT triggers classification, this variable holds the result so… |
CLAUDE_CODE_CLIENT_CERTAuthentication | Present since v2.1.69 or earlier Documented | Path to client certificate for mTLS |
CLAUDE_CODE_CLIENT_DATA_URLNetwork and proxy | Added between v2.1.269 and v2.1.283 | URL of a signed configuration document on downloads.claude.ai with per-model client data; same as --client-data-url, and keeps the URL out of the process list.… |
CLAUDE_CODE_CLIENT_KEYAuthentication | Present since v2.1.69 or earlier Documented | Path to client private key |
CLAUDE_CODE_CLIENT_KEYPMAuthentication | Removed between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_CLIENT_KEY_PASSPHRASEAuthentication | Present since v2.1.69 or earlier Documented | Passphrase for encrypted client key |
CLAUDE_CODE_CLOUD_SESSION_IDSessions | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_COLD_COMPACTContext and compaction | Added between v2.1.123 and v2.1.126 | — |
CLAUDE_CODE_COMMIT_BETWEEN_KEYSOther | Removed in v2.1.284 | — |
CLAUDE_CODE_COMMIT_LOGDebugging | Removed between v2.1.224 and v2.1.227 | Likely controls whether or where Claude Code logs commit operations. This could enable audit trails for automated commits made by agents and sub-agents —… |
CLAUDE_CODE_COMPILED_ACORNOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_CONFIG_PROBEOther | Added in v2.1.286 | — |
CLAUDE_CODE_CONFIG_WATCH_EVENTSOther | Added in v2.1.288 | — |
CLAUDE_CODE_CONNECT_TIMEOUT_MSNetwork and proxy | Added between v2.1.266 and v2.1.269 Documented | — |
CLAUDE_CODE_CONSENT_POINTERLESSOther | Added in v2.1.305 | — |
CLAUDE_CODE_CONTAINER_IDOther | Removed in v2.1.310 | Container/pod identifier sent in HTTP headers |
CLAUDE_CODE_COORDINATOR_EXTRA_TOOLSAgents and subagents | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_COORDINATOR_FORCE_WORKER_INHERIT_MODELAgents and subagents | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_COORDINATOR_MODEAgents and subagents | Added between v2.1.143 and v2.1.212 | Runs a session as a coordinator over child agents, with companions for its toolset and whether memory flows down the tree. The agent-teams plumbing that was… |
CLAUDE_CODE_COORDINATOR_PROPAGATE_NESTED_MEMORYAgents and subagents | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_COORDINATOR_SKILL_GUIDANCEAgents and subagents | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_COORDINATOR_WORKER_CHECKIN_SECONDSAgents and subagents | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_COWORK_FRAME_ARTIFACTSOther | Added in v2.1.228 | — |
CLAUDE_CODE_COZY_TEAPOTOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_CURRIED_TRINKETOther | Added in v2.1.290 | — |
CLAUDE_CODE_CUSTOM_OAUTH_URLAuthentication | Removed in v2.1.310 | Custom OAuth endpoint URL |
CLAUDE_CODE_DAEMON_COLD_STARTOther | Added between v2.1.118 and v2.1.123 | Set when the daemon starts from a completely cold state rather than resuming warm. Lets the daemon emit different startup telemetry and skip cache-warm… |
CLAUDE_CODE_DAPPER_CUPCAKEOther | Added in v2.1.301 | — |
CLAUDE_CODE_DAPPER_LAGOONOther | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_DATADOG_FLUSH_INTERVAL_MSTelemetry | Present since v2.1.69 or earlier | Datadog metrics flush interval (ms) |
CLAUDE_CODE_DD_ERROR_TRACKING_FLUSH_INTERVAL_MSTelemetry | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DEBUG_LOGS_DIRDebugging | Present since v2.1.69 or earlier Documented | Custom directory for debug logs |
CLAUDE_CODE_DEBUG_LOG_LEVELDebugging | Added between v2.1.70 and v2.1.72 Documented | Set debug logging verbosity level. More granular than the existing DEBUG=1 boolean — probably accepts levels like "info", "warn", "error", "debug". |
CLAUDE_CODE_DEBUG_REPAINTSDebugging | Added between v2.1.79 and v2.1.83 | Enables debug logging for terminal repaint operations. This release fixes several rendering issues — screen flashing blank after idle, scrollback jumping when… |
CLAUDE_CODE_DECSTBMOther | Added between v2.1.108 and v2.1.114 | Enables DECSTBM (VT100 Set Top and Bottom Margins) for scrolling regions in the TUI. The mechanism behind /tui fullscreen's flicker-free rendering — pins… |
CLAUDE_CODE_DESIGN_OAUTH_CLIENT_IDAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DESKTOP_APP_VERSIONOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_DESKTOP_CONNECTOR_NAMESNetwork and proxy | Added in v2.1.310 | Carries desktop connector names into the session from the host. It is read once at startup, applied, then cleared from the environment. New in v2.1.310. |
CLAUDE_CODE_DESKTOP_SKILLS_PLUGIN_DIRPlugins and skills | Added between v2.1.301 and v2.1.303 | Holds a directory path the desktop app passes for its skills plugin; the client reads it into the desktop-skills plugin directory, then clears it from the… |
CLAUDE_CODE_DESKTOP_SKILL_SWITCHESPlugins and skills | Added in v2.1.293 | — |
CLAUDE_CODE_DEV_RAW_CHANGELOG_URLNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DIAGNOSTICS_FILEOther | Removed in v2.1.290 | Path to write diagnostics output |
CLAUDE_CODE_DIFF_COPY_ROOTOther | Added in v2.1.307 | A self-hosted runner names, in this variable, the folder holding the checked copy of a repository's git settings that Claude Code reads for a workspace diff… |
CLAUDE_CODE_DIR_SYNC_ARCHIVEOther | Removed between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_DIR_SYNC_DISABLE_ANCHORINGFeature toggles | Removed in v2.1.285 | — |
CLAUDE_CODE_DIR_SYNC_ENGINEOther | Removed in v2.1.285 | — |
CLAUDE_CODE_DIR_SYNC_FFWDOther | Removed in v2.1.285 | — |
CLAUDE_CODE_DIR_SYNC_GITOther | Removed in v2.1.285 | — |
CLAUDE_CODE_DIR_SYNC_OVERLAYOther | Removed between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_DIR_SYNC_STREAMNetwork and proxy | Removed in v2.1.285 | — |
CLAUDE_CODE_DISABLE_1M_CONTEXTContext and compaction | Present since v2.1.69 or earlier Documented | Disable extended 1M token context window |
CLAUDE_CODE_DISABLE_ADAPTIVE_THINKINGModels and thinking | Present since v2.1.69 or earlier Documented | Disable adaptive thinking mode |
CLAUDE_CODE_DISABLE_ADMIN_ENV_UNIONFeature toggles | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_CODE_DISABLE_ADVISOR_TOOLShell and tools | Added between v2.1.79 and v2.1.83 Documented | Disables what appears to be an internal advisory tool. The "Advisor" pattern suggests a meta-tool that provides guidance or recommendations to the model during… |
CLAUDE_CODE_DISABLE_AGENTS_FLEETAgents and subagents | Removed between v2.1.138 and v2.1.143 | Kill switch for the entire agent fleet subsystem — no selection, no auto-relaunch, no fleet coordination. Its existence implies the fleet is on by default for… |
CLAUDE_CODE_DISABLE_AGENT_VIEWAgents and subagents | Added between v2.1.138 and v2.1.143 Documented | Disables Agent View. Renamed successor to CLAUDE_CODE_DISABLE_AGENTS_FLEET (removed this release). If you're managing Claude Code via policy config and aren't… |
CLAUDE_CODE_DISABLE_ALTERNATE_SCREENTerminal and UI | Added between v2.1.128 and v2.1.138 Documented | Prevents the TUI from using the terminal alternate screen buffer. If Claude Code's UI is eating your terminal history, breaking tmux scrollback, or failing in… |
CLAUDE_CODE_DISABLE_ARTIFACTFeature toggles | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_ATTACHMENTSFeature toggles | Present since v2.1.69 or earlier Documented | File/image attachments |
CLAUDE_CODE_DISABLE_ATTRIBUTION_BASELINE_REUSEFeature toggles | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_DISABLE_ATTRIBUTION_CROSS_REPOFeature toggles | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_DISABLE_AUTH_REFRESH_LOCKAuthentication | Added in v2.1.286 Documented | Turns off the lock that coordinates a GCP or AWS credential refresh across processes. With the lock on, one process refreshes and opens a single login browser… |
CLAUDE_CODE_DISABLE_AUTO_MEMORYMemory and CLAUDE.md | Present since v2.1.69 or earlier Documented | Disable automatic memory (MEMORY.md) |
CLAUDE_CODE_DISABLE_AWAITING_USER_IDLEFeature toggles | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_DISABLE_BACKGROUND_TASKSSessions | Present since v2.1.69 or earlier Documented | Disable background tasks entirely |
CLAUDE_CODE_DISABLE_BEDROCK_CONTENT_TYPE_DEFAULTCloud providers | Removed between v2.1.245 and v2.1.247 Documented | — |
CLAUDE_CODE_DISABLE_BEDROCK_CONTENT_TYPE_GUARDCloud providers | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_BG_EXIT_HANDOFFSessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_BG_SHELL_PRESSURE_REAPShell and tools | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_BG_STABLE_PATHSessions | Added in v2.1.295 | — |
CLAUDE_CODE_DISABLE_BUNDLED_SKILLSPlugins and skills | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_CFC_PROMPTFeature toggles | Added between v2.1.252 and v2.1.266 Documented | — |
CLAUDE_CODE_DISABLE_CLAUDE_API_SKILLPlugins and skills | Removed between v2.1.252 and v2.1.266 | Disables the built-in Claude API skill. The Claude API skill auto-triggers when code imports anthropic or @anthropic-ai/sdk, providing SDK-aware guidance. In… |
CLAUDE_CODE_DISABLE_CLAUDE_CODE_SKILLPlugins and skills | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DISABLE_CLAUDE_MDSMemory and CLAUDE.md | Present since v2.1.69 or earlier Documented | Disable loading CLAUDE.md files |
CLAUDE_CODE_DISABLE_COMMAND_INJECTION_CHECKFeature toggles | Removed between v2.1.88 and v2.1.89 | Previously allowed disabling command injection detection. The safety check is now mandatory — no opt-out. This aligns with the changelog's hook hardening:… |
CLAUDE_CODE_DISABLE_CRONFeature toggles | Removed in v2.1.310 Documented | Disable cron/scheduled task functionality. Claude Code recently added /cron for recurring tasks — this lets you turn it off entirely. |
CLAUDE_CODE_DISABLE_DANGEROUS_RM_TIMEOUTNetwork and proxy | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_DISABLE_DIR_SYNCFeature toggles | Removed in v2.1.285 | — |
CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETASFeature toggles | Present since v2.1.69 or earlier Documented | Experimental beta API features |
CLAUDE_CODE_DISABLE_EXPLORE_INHERIT_CAPFeature toggles | Added between v2.1.215 and v2.1.217 | Lets the built-in Explore search agent run at the parent model instead of a cheaper capped default. First shipped v2.1.217; undocumented. |
CLAUDE_CODE_DISABLE_EXPLORE_PLAN_AGENTSAgents and subagents | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_FAST_MODEModels and thinking | Present since v2.1.69 or earlier Documented | Disable the /fast toggle that uses the same model with faster output |
CLAUDE_CODE_DISABLE_FEEDBACK_SURVEYTelemetry | Present since v2.1.69 or earlier Documented | Survey prompts |
CLAUDE_CODE_DISABLE_FILE_CHECKPOINTINGFeature toggles | Present since v2.1.69 or earlier Documented | Git-based file checkpointing/backup |
CLAUDE_CODE_DISABLE_FILE_MENTIONSFeature toggles | Added in v2.1.299 Documented | Switches @ file mentions from inlining file contents to passing their paths, which Claude reads with its file tools on demand. Keeps large mentioned files out… |
CLAUDE_CODE_DISABLE_GIT_INSTRUCTIONSFeature toggles | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_DISABLE_HOME_SETTINGS_SEEDFeature toggles | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_DISABLE_HOOK_FORWARDINGFeature toggles | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_DISABLE_INLINE_SHELL_RM_PROMPTShell and tools | Added in v2.1.288 Documented | Turns off the new prompt that catches a dangerous rm inside an inline bash -c or sh -c script. Left unset, such a command asks before running even under… |
CLAUDE_CODE_DISABLE_LAUNCHER_SIGN_INFeature toggles | Removed in v2.1.310 | When set, the launcher sign-in path reports switched_off and does not offer launcher sign-in. |
CLAUDE_CODE_DISABLE_LAUNCH_COMPOSERFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DISABLE_LEGACY_MODEL_REMAPModels and thinking | Present since v2.1.69 or earlier Documented | — |
CLAUDE_CODE_DISABLE_MCP_TASK_BACKGROUNDMCP | Added between v2.1.247 and v2.1.252 Documented | — |
CLAUDE_CODE_DISABLE_MEMORY_BULK_INFLATEMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DISABLE_MEMORY_MASS_DELETE_HOLDMemory and CLAUDE.md | Added in v2.1.218 | — |
CLAUDE_CODE_DISABLE_MEMORY_PERIODIC_RESYNCMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DISABLE_MEMORY_RO_UNSAVED_NOTICEMemory and CLAUDE.md | Removed between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_DISABLE_MEMORY_STREAM_LISTNetwork and proxy | Added between v2.1.143 and v2.1.212 | Turns off the incremental metadata-streaming path inside multi-store memory sync. That path (gated by the new tengu_memory_stream_list, default on) calls a… |
CLAUDE_CODE_DISABLE_MODEL_ACCESS_FALLBACKModels and thinking | Added in v2.1.285 Documented | Present in the v2.1.285 build and absent from that release's notes. |
CLAUDE_CODE_DISABLE_MOUNTED_DRIVE_RM_PROMPTFeature toggles | Added in v2.1.304 Documented | Turns off the dangerous-removal prompt this release adds for an rm that targets a mounted drive, the folder that holds mounted drives, or a top-level entry of… |
CLAUDE_CODE_DISABLE_MOUSETerminal and UI | Added between v2.1.87 and v2.1.88 Documented | Disables all mouse input handling in the terminal UI. Claude Code captures mouse events for interactive elements like clickable buttons and text selection, but… |
CLAUDE_CODE_DISABLE_MOUSE_CLICKSTerminal and UI | Removed in v2.1.310 Documented | Granular mouse click disable, added in v2.1.88. Superseded by the broader CLAUDE_CODE_DISABLE_MOUSE flag. The two-tier mouse control approach lasted one… |
CLAUDE_CODE_DISABLE_MTLS_RELOAD_ON_STALE_CONNECTIONNetwork and proxy | Added between v2.1.229 and v2.1.234 Documented | — |
CLAUDE_CODE_DISABLE_NESTED_CHAIN_IDLEFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DISABLE_NESTED_USER_REPAIRFeature toggles | Added in v2.1.238 | — |
CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFICFeature toggles | Removed in v2.1.287 Documented | Non-critical network requests |
CLAUDE_CODE_DISABLE_NONSTREAMING_FALLBACKNetwork and proxy | Added between v2.1.79 and v2.1.83 Documented | Disables the fallback path that retries failed streaming requests as non-streaming calls. The changelog explicitly documents this variable. |
CLAUDE_CODE_DISABLE_NOTIFICATION_PRESENCE_CHECKFeature toggles | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_OFFICIAL_MARKETPLACE_AUTOINSTALLPlugins and skills | Present since v2.1.69 or earlier Documented | Disable automatic plugin installation from marketplace |
CLAUDE_CODE_DISABLE_ORG_MEMORYMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | Kill switch for a new organization-scoped memory subsystem. The sync entrypoint returns early — disabled — the moment this variable is set. |
CLAUDE_CODE_DISABLE_PERMISSION_PROMPT_NOTIFY_HOOKSPermissions and sandbox | Added between v2.1.229 and v2.1.234 Documented | — |
CLAUDE_CODE_DISABLE_PLUGIN_FORWARDINGPlugins and skills | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_DISABLE_POLICY_SKILLSPlugins and skills | Added between v2.1.87 and v2.1.88 Documented | Disables policy-enforced skills. Skills in Claude Code are specialized prompt-driven capabilities (like /commit or /review-pr) that can be configured at the… |
CLAUDE_CODE_DISABLE_POWERSHELL_CMD_RM_DENYShell and tools | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_DISABLE_PRECOMPACT_SKIPContext and compaction | Present since v2.1.69 or earlier | Disable skipping pre-compaction checks |
CLAUDE_CODE_DISABLE_PROACTIVITYFeature toggles | Added in v2.1.290 | Turns off the proactivity selector, a behavior gated by tengu_proactivity_selector and on by default. When set, the value is carried into relaunched and… |
CLAUDE_CODE_DISABLE_REFUSAL_FALLBACKFeature toggles | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_DISABLE_REFUSAL_RETRYNetwork and proxy | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_DISABLE_STARTUP_WORK_GATEFeature toggles | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_DISABLE_STRUCTURED_OUTPUTSFeature toggles | Added in v2.1.288 Documented | Turns structured outputs off for gateways or providers (such as Mantle) that reject them. The changelog ties this to session titles, memory recall and prompt… |
CLAUDE_CODE_DISABLE_SUBSTITUTION_RM_PROMPTFeature toggles | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_DISABLE_TERMINAL_TITLETerminal and UI | Present since v2.1.69 or earlier Documented | Stop Claude Code from setting the terminal title |
CLAUDE_CODE_DISABLE_THINKINGModels and thinking | Removed in v2.1.310 Documented | Completely disable extended thinking |
CLAUDE_CODE_DISABLE_TURN_HANDOFFFeature toggles | Removed in v2.1.310 | — |
CLAUDE_CODE_DISABLE_ULTRAREVIEW_TRUST_CHECKFeature toggles | Added between v2.1.307 and v2.1.309 Documented | Set to 1 to skip the workspace-trust gate that claude ultrareview added in v2.1.309. Without it, ultrareview asks for trust on a terminal or refuses to run;… |
CLAUDE_CODE_DISABLE_UNKNOWN_MODEL_WINDOW_ENFORCEMENTModels and thinking | Added between v2.1.222 and v2.1.224 Documented | — |
CLAUDE_CODE_DISABLE_VIRTUAL_SCROLLTerminal and UI | Added between v2.1.70 and v2.1.72 Documented | Disable virtual scrolling in terminal UI. Useful if virtual scroll causes rendering issues in certain terminal emulators or when piping output. |
CLAUDE_CODE_DISABLE_VITALS_EMITTERFeature toggles | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_DISABLE_WEB_FETCHShell and tools | Added in v2.1.285 Documented | Turns off the WebFetch tool. An environment variable, so it disables WebFetch without a managed-settings file. Added in v2.1.285. |
CLAUDE_CODE_DISABLE_WINDOWS_SHELL_LAUNCHERShell and tools | Added between v2.1.266 and v2.1.269 Documented | — |
CLAUDE_CODE_DISABLE_WORKFLOWSAgents and subagents | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_DISABLE_WORKING_SYNCFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_DISPATCH_V2DOther | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_DISPATCH_V2SOther | Added in v2.1.219 | — |
CLAUDE_CODE_DONT_INHERIT_ENVOther | Removed between v2.1.307 and v2.1.309 | Start shell with empty environment |
CLAUDE_CODE_DOWNLOAD_DEADLINE_MS_FOR_TESTINGOther | Removed in v2.1.310 | — |
CLAUDE_CODE_EAGER_FLUSHOther | Present since v2.1.69 or earlier | Eagerly flush output buffers |
CLAUDE_CODE_EDITOR_CODELIVERYOther | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_EFFORT_LEVELModels and thinking | Present since v2.1.69 or earlier Documented | Reasoning effort: low, medium, or high (default). Controls adaptive thinking depth [4] |
CLAUDE_CODE_ELEGANT_MEADOWOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_EMIT_SESSION_STATE_EVENTSSessions | Added between v2.1.79 and v2.1.83 Documented | Controls whether Claude Code emits session state change events. This fits the growing SDK and Remote Control infrastructure — external consumers (IDE… |
CLAUDE_CODE_EMIT_STARTUP_TIMINGOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_EMIT_TOOL_USE_SUMMARIESShell and tools | Present since v2.1.69 or earlier | Emit tool use summary events |
CLAUDE_CODE_ENABLE_APPEND_SUBAGENT_PROMPTAgents and subagents | Added between v2.1.108 and v2.1.114 | Authorizes SDK callers to append a custom string to a subagent's system prompt via options.appendSubagentSystemPrompt. Without this flag, the option is… |
CLAUDE_CODE_ENABLE_AUTO_MODEPermissions and sandbox | Added between v2.1.143 and v2.1.212 Documented | The master switch. Redundant on Bedrock/Vertex/Foundry now that Auto mode is default-on, but still the toggle everywhere else. It gates everything below. |
CLAUDE_CODE_ENABLE_AWAY_SUMMARYFeature toggles | Added between v2.1.104 and v2.1.107 Documented | Enables generation of a summary when the user returns after being away from an active session. |
CLAUDE_CODE_ENABLE_BACKGROUND_PLUGIN_REFRESHPlugins and skills | Added between v2.1.108 and v2.1.114 Documented | Enables automatic background plugin refresh when the runtime detects updates are needed. Without this, refresh is synchronous and delays session startup. |
CLAUDE_CODE_ENABLE_CFCFeature toggles | Present since v2.1.69 or earlier Documented | Enable Claude for Chrome browser automation |
CLAUDE_CODE_ENABLE_DESIGN_SYNCFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ENABLE_EXPERIMENTAL_ADVISOR_TOOLShell and tools | Removed in v2.1.310 | Enables the experimental Advisor Tool — a server-side tool with its own advisorModel config option. Requires first-party auth; falls back to the… |
CLAUDE_CODE_ENABLE_FEEDBACK_SURVEY_FOR_OTELTelemetry | Added between v2.1.128 and v2.1.138 Documented | Re-enables the session quality survey for enterprise deployments with OTEL enabled. Backs the v2.1.136 changelog bullet explicitly. If your org collects Claude… |
CLAUDE_CODE_ENABLE_FINE_GRAINED_TOOL_STREAMINGNetwork and proxy | Present since v2.1.69 or earlier Documented | Enable fine-grained (eager) input streaming for tools |
CLAUDE_CODE_ENABLE_FUNCTION_HOOKSFeature toggles | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_ENABLE_GATEWAY_MODEL_DISCOVERYModels and thinking | Added between v2.1.128 and v2.1.138 Documented | Query available models from a gateway rather than a hardcoded list. For enterprise setups where model availability is controlled centrally — a new model rolls… |
CLAUDE_CODE_ENABLE_LAUNCH_COMPOSERFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ENABLE_MENU_KIND_LANESFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ENABLE_MORNING_BRIEFFeature toggles | Removed between v2.1.212 and v2.1.215 | — |
CLAUDE_CODE_ENABLE_NARRATIONFeature toggles | Removed in v2.1.284 | — |
CLAUDE_CODE_ENABLE_OPUS_4_7_FAST_MODEModels and thinking | Added between v2.1.128 and v2.1.138 Documented | — |
CLAUDE_CODE_ENABLE_PROMPT_SUGGESTIONFeature toggles | Removed in v2.1.310 Documented | Enables a prompt suggestion feature in the Claude Code UI. This likely surfaces contextual follow-up prompts or autocomplete suggestions based on the current… |
CLAUDE_CODE_ENABLE_PROXY_AUTH_HELPERAuthentication | Added between v2.1.108 and v2.1.114 | Set to "1" to enable the proxy auth helper subsystem. Lets Claude Code shell out to an external program to fetch proxy credentials dynamically — for… |
CLAUDE_CODE_ENABLE_REFRESH_MCP_TOOLSMCP | Added between v2.1.143 and v2.1.212 | Enables an on-demand MCP-tool refresh capability, grouped with CLAUDE_CODE_ENABLE_TASKS and CLAUDE_CODE_ENABLE_REMOTE_RECAP. It lets a session re-fetch an MCP… |
CLAUDE_CODE_ENABLE_REMOTE_RECAPSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_ENABLE_SDK_FILE_CHECKPOINTINGFeature toggles | Present since v2.1.69 or earlier | Enable file checkpointing in SDK mode |
CLAUDE_CODE_ENABLE_SHARE_BUNDLEFeature toggles | Added in v2.1.299 Documented | — |
CLAUDE_CODE_ENABLE_TASKSFeature toggles | Present since v2.1.69 or earlier Documented | Enable the task system |
CLAUDE_CODE_ENABLE_TELEMETRYTelemetry | Present since v2.1.69 or earlier Documented | Enable telemetry collection |
CLAUDE_CODE_ENABLE_TODO_TOOLSShell and tools | Added between v2.1.229 and v2.1.234 Documented | — |
CLAUDE_CODE_ENABLE_TOKEN_USAGE_ATTACHMENTAuthentication | Present since v2.1.69 or earlier | Attach token usage info to messages |
CLAUDE_CODE_ENABLE_XAAFeature toggles | Added between v2.1.79 and v2.1.83 | Enables an internal feature flagged as "XAA." The acronym is opaque, but the ENABLE_ prefix and proximity to other experimental flags suggest this is an opt-in… |
CLAUDE_CODE_ENHANCED_TELEMETRY_BETATelemetry | Present since v2.1.69 or earlier | Enable enhanced telemetry (beta) |
CLAUDE_CODE_ENTRYPOINTOther | Present since v2.1.69 or earlier | Application entry point; auto-set based on context (e.g. cli, vscode, sdk-py) [7] |
CLAUDE_CODE_ENTRYPOINT_ON_REQUESTSOther | Added in v2.1.305 | — |
CLAUDE_CODE_ENVIRONMENT_KINDOther | Removed in v2.1.310 | Environment: byoc, anthropic_cloud, bridge |
CLAUDE_CODE_ENVIRONMENT_RUNNER_VERSIONOther | Added between v2.1.143 and v2.1.212 | Environment runner version |
CLAUDE_CODE_EVAL_ALLOW_ARTIFACT_PUBLISHOther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_EVAL_ALLOW_FLAG_OVERRIDESTerminal and UI | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_EVAL_ARTIFACT_STUB_DIROther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_EVAL_CONFINEDOther | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_EVAL_INTERVIEW_SESSIONSessions | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_EXECPATHOther | Added in v2.1.92 | Overrides the detected executable path for the Claude Code binary. This matters in environments where the binary is symlinked, wrapped in a shell script, or… |
CLAUDE_CODE_EXIT_AFTER_FIRST_RENDEROther | Present since v2.1.69 or earlier | Exit after first UI render (testing) |
CLAUDE_CODE_EXIT_AFTER_STOP_DELAYOther | Present since v2.1.69 or earlier Documented | Delay before exit after stop signal (ms) |
CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMSAgents and subagents | Removed in v2.1.310 Documented | Enable Agent Teams (the official release of Swarms). Each agent works in an independent Git Worktree [1] |
CLAUDE_CODE_EXPERIMENTAL_OBSERVER_AGENTSAgents and subagents | Added between v2.1.143 and v2.1.212 | Agents that watch a session rather than act in it. The natural counterpart to autonomy: if agents edit on their own, you want independent observers checking… |
CLAUDE_CODE_EXTRA_BODYOther | Present since v2.1.69 or earlier Documented | Additional JSON merged into API request bodies |
CLAUDE_CODE_EXTRA_METADATAOther | Added between v2.1.77 and v2.1.79 | Passes additional metadata to API requests beyond what Claude Code includes by default. This likely attaches custom key-value pairs to the Anthropic API call… |
CLAUDE_CODE_FABLE_BRIDGE_DIALOG_TIMEOUT_MSNetwork and proxy | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_FEDERATION_CACHE_DIROther | Removed in v2.1.310 | — |
CLAUDE_CODE_FILE_READ_MAX_OUTPUT_TOKENSContext and compaction | Present since v2.1.69 or earlier Documented | Max tokens for file read output |
CLAUDE_CODE_FILE_READ_MAX_PDF_PAGES_PER_MESSAGEOther | Added in v2.1.300 | Caps how many PDF pages the Read tool loads within a single message. A value below the built-in limit trims the pages pulled in per message. |
CLAUDE_CODE_FILE_READ_MAX_PDF_PAGES_PER_TURNOther | Added in v2.1.300 | Caps the running total of PDF pages the Read tool loads across a turn, working with the per-message cap above. |
CLAUDE_CODE_FLAG_FETCH_WAIT_MSOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_FLEETVIEW_SIMPLEOther | Removed in v2.1.310 | Forces the simplified FleetView layout, the multi-agent monitoring surface. First shipped v2.1.216; undocumented. |
CLAUDE_CODE_FLEET_PAST_SESSIONSSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_FOOTER_INDICATOROther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_FORCE_BRIDGESessions | Removed between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_FORCE_EVALUATE_MEMORYMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_FORCE_FIRST_LAUNCHFeature toggles | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_FORCE_FULLSCREEN_UPSELLTerminal and UI | Added between v2.1.108 and v2.1.114 | Forces the fullscreen TUI upsell prompt past the normal fullscreenUpsellSeenCount cap and the tengu_ochre_hollow gate. Internal test/demo affordance. |
CLAUDE_CODE_FORCE_FULL_LOGODebugging | Removed between v2.1.245 and v2.1.247 | Force full ASCII logo display on startup |
CLAUDE_CODE_FORCE_GLOBAL_CACHEShell and tools | Removed between v2.1.87 and v2.1.88 | Previously forced use of a global cache directory. Likely superseded by improved cache management that no longer needs a manual override. |
CLAUDE_CODE_FORCE_MEMORY_SURVEYMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_FORCE_MID_CONVERSATION_SYSTEMFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_FORCE_RC_LONG_TURN_NUDGEFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_FORCE_SANDBOXPermissions and sandbox | Removed in v2.1.300 | — |
CLAUDE_CODE_FORCE_SESSION_PERSISTENCESessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_FORCE_STRIKETHROUGHFeature toggles | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_FORCE_SYNC_OUTPUTFeature toggles | Added between v2.1.128 and v2.1.138 Documented | Disable streaming output in favor of synchronous writes. If you're capturing Claude Code output in a script and seeing partial lines or buffering artifacts,… |
CLAUDE_CODE_FORCE_TERMINAL_IMAGESTerminal and UI | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_FORCE_TIP_IDFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_FORCE_WINDOWS_CREDMANFeature toggles | Added between v2.1.143 and v2.1.212 | Forces credential storage through the Windows Credential Manager. A FORCE_ override in the credential-backend family next to… |
CLAUDE_CODE_FORK_SUBAGENTAgents and subagents | Added between v2.1.114 and v2.1.117 Documented | Changelog-confirmed[1]: set to 1 to run subagents as forked processes (v2.1.117 on external builds, v2.1.121 extended to non-interactive SDK/-p sessions).… |
CLAUDE_CODE_FORWARD_SUBAGENT_TEXTAgents and subagents | Added between v2.1.143 and v2.1.212 Documented | Includes subagent text and thinking in stream-json output, paired with a new --forward-subagent-text flag. Shipped in v2.1.211 (npm 2026-07-15) and the one… |
CLAUDE_CODE_FORWARD_USER_INTENTOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_FOUND_REPOSITORY_GITOther | Added in v2.1.307 | — |
CLAUDE_CODE_FRAME_TIMING_LOGDebugging | Removed between v2.1.269 and v2.1.283 | Enable per-frame render timing logs in the terminal UI. A diagnostic variable — when set, it likely writes timing data for each UI frame render cycle, useful… |
CLAUDE_CODE_FRAME_TIMING_SAMPLE_EVERYOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_GATEWAY_HINT_HEADERSOther | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_GATEWAY_MODEL_DISCOVERY_TIMEOUT_MSNetwork and proxy | Added between v2.1.266 and v2.1.269 Documented | — |
CLAUDE_CODE_GATEWAY_TOKENAuthentication | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_GATEWAY_TOKEN_FILE_DESCRIPTORAuthentication | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_GAULT_KESTRELOther | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_GB_BASE_URLNetwork and proxy | Present since v2.1.69 or earlier | An internal base URL override, possibly for a "gradebook" or grading service used during internal testing. Its removal suggests the endpoint was consolidated… |
CLAUDE_CODE_GB_DISK_CACHE_WHEN_TELEMETRY_OFFTelemetry | Added between v2.1.143 and v2.1.212 | Opts GrowthBook (GB) flag data back into the on-disk cache under a telemetry-off profile, where feature-flag caching would otherwise be skipped. Shipped… |
CLAUDE_CODE_GB_REFRESH_INTERVAL_MSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_GENTLE_PARASOLOther | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_GIT_BASH_PATHShell and tools | Present since v2.1.69 or earlier Documented | Git Bash executable path (Windows) |
CLAUDE_CODE_GLOB_HIDDENShell and tools | Present since v2.1.69 or earlier Documented | Include hidden files in globs |
CLAUDE_CODE_GLOB_NO_IGNOREShell and tools | Present since v2.1.69 or earlier Documented | Ignore .gitignore rules in globs |
CLAUDE_CODE_GLOB_TIMEOUT_SECONDSNetwork and proxy | Present since v2.1.69 or earlier Documented | Timeout for glob operations; default 20s (WSL: 60s) |
CLAUDE_CODE_GOAL_CHECKIN_MINUTESOther | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_GORSE_PLOVEROther | Removed in v2.1.310 | — |
CLAUDE_CODE_GROWTHBOOK_KICK_FROM_INITOther | Added in v2.1.287 | — |
CLAUDE_CODE_GROWTHBOOK_KICK_ON_WARM_CACHEOther | Added in v2.1.288 | — |
CLAUDE_CODE_GZIP_CCR_REQUEST_BODIESNetwork and proxy | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_GZIP_DATADOG_LOGSTelemetry | Added in v2.1.288 | — |
CLAUDE_CODE_GZIP_REQUEST_BODIESNetwork and proxy | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_GZIP_REQUEST_BODY_BLOCKSNetwork and proxy | Removed in v2.1.310 | Selects one of two gzip modes (1 or 2) for API request bodies at least 512KB in size; any other value, and the default, leaves it off. It sits alongside the… |
CLAUDE_CODE_GZIP_REQUEST_BODY_LEVELNetwork and proxy | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_HANDBACK_PROVENANCEOther | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_HARBOR_KITEOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_CODE_HARBOR_KITE_CLOUDOther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_HARBOR_KITE_PACING_OFFOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_HARMONIC_RIDDLEOther | Added in v2.1.290 | — |
CLAUDE_CODE_HERON_TALLOWOther | Removed in v2.1.229 | — |
CLAUDE_CODE_HFI_BEARER_TOKENAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_HIDE_CWDTerminal and UI | Added between v2.1.118 and v2.1.123 Documented | Changelog-confirmed[1] (v2.1.119): hides the working directory display in the startup logo. Useful for shared terminals, screen shares, or documentation… |
CLAUDE_CODE_HIDE_REPLY_SERVER_NAMETerminal and UI | Added in v2.1.300 | When the app's own tool server (the one that serves the tools you reply with) cannot sign in, this hides that server's name from Claude, so it does not name or… |
CLAUDE_CODE_HIDE_SETTINGS_HINTTerminal and UI | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_HOLD_REPORT_PARK_AT_INITOther | Removed in v2.1.310 | — |
CLAUDE_CODE_HOLD_UNANSWERED_PARKED_PERMISSIONPermissions and sandbox | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_HOME_SEED_HOLD_TIMEOUT_MSNetwork and proxy | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_HOME_SEED_VERDICT_TIMEOUT_MSNetwork and proxy | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_HOOKS_SAME_THREADOther | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_HOSTED_DESKTOPOther | Added in v2.1.290 | — |
CLAUDE_CODE_HOST_AUTH_ENV_VARAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_HOST_AUTH_REFRESH_TIMEOUT_MSAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_HOST_CREDS_FILEOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_HOST_GATEWAY_LINEAGEOther | Removed in v2.1.310 | — |
CLAUDE_CODE_HOST_HTTP_PROXY_PORTNetwork and proxy | Removed between v2.1.245 and v2.1.247 | HTTP proxy port for host |
CLAUDE_CODE_HOST_PLATFORMOther | Present since v2.1.69 or earlier | Override platform detection: win32, darwin, linux |
CLAUDE_CODE_HOST_PROMPT_SUPERSEDES_RECORDOther | Added in v2.1.285 | — |
CLAUDE_CODE_HOST_SCHEDULED_RUNOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_HOST_SESSION_IDSessions | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_HOST_SKILL_CATALOGPlugins and skills | Added in v2.1.292 | A JSON object ({"skills": [...]}) of 1 to 64 folder names that scopes which synced claude.ai skills a remote session loads. It is read only when a remote… |
CLAUDE_CODE_HOST_SOCKS_PROXY_PORTNetwork and proxy | Present since v2.1.69 or earlier | SOCKS proxy port for host |
CLAUDE_CODE_HOST_WORKTREEOther | Added in v2.1.288 | — |
CLAUDE_CODE_HOST_WORKTREE_FENCEOther | Added in v2.1.288 | — |
CLAUDE_CODE_HOVER_RESTOther | Added in v2.1.238 | — |
CLAUDE_CODE_HTTPS_PROXYNetwork and proxy | Added between v2.1.114 and v2.1.117 | Claude-namespaced HTTPS proxy URL. See CLAUDE_CODE_HTTP_PROXY above. |
CLAUDE_CODE_HTTP_PROXYNetwork and proxy | Added between v2.1.114 and v2.1.117 | Claude-namespaced HTTP proxy URL. Claude-namespacing avoids collisions with system HTTP_PROXY for other tools in the shell that should use a different proxy.… |
CLAUDE_CODE_HUMBLE_HAMMOCKOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_IDE_HOST_OVERRIDETerminal and UI | Present since v2.1.69 or earlier Documented | Custom host address for IDE communication |
CLAUDE_CODE_IDE_SKIP_AUTO_INSTALLTerminal and UI | Present since v2.1.69 or earlier Documented | Skip automatic IDE extension install |
CLAUDE_CODE_IDE_SKIP_VALID_CHECKTerminal and UI | Removed in v2.1.310 Documented | Bypass IDE extension validation checks |
CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENSContext and compaction | Added in v2.1.290 Documented | Sets the minimum conversation size, in tokens, before idle compaction runs. The value is floored at 100,000 and defaults to 200,000 when unset. |
CLAUDE_CODE_IDLE_THRESHOLD_MINUTESOther | Added in v2.1.84 | Sets the threshold (in minutes) before a session is considered idle. The changelog describes a new "idle-return prompt" that nudges users returning after 75+… |
CLAUDE_CODE_IDLE_TOKEN_THRESHOLDAuthentication | Removed between v2.1.245 and v2.1.247 | Works alongside CLAUDE_CODE_IDLE_THRESHOLD_MINUTES to gate when the idle-return prompt appears. The token threshold likely ensures the prompt only fires for… |
CLAUDE_CODE_IGNORE_PERSISTED_TRUSTOther | Added in v2.1.307 | When set, no persisted workspace-trust record counts in the process. A self-hosted runner sets it when started with --trust-workspace false. |
CLAUDE_CODE_INCLUDE_PARTIAL_MESSAGESOther | Present since v2.1.69 or earlier | Include partial/streaming messages in output |
CLAUDE_CODE_INLINE_TOOLSShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_INSTALLED_VIA_NPM_WRAPPEROther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_INTRO_FRAMEOther | Removed in v2.1.295 | — |
CLAUDE_CODE_INVESTIGATE_FIRSTOther | Removed between v2.1.222 and v2.1.224 | Instructs the agent to read and investigate before acting — enforcing "read before write." Converts an agent that might immediately start editing into one that… |
CLAUDE_CODE_INVOKED_SKILLSPlugins and skills | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_IS_COWORKOther | Present since v2.1.69 or earlier | Indicates running in cowork (multi-agent) mode |
CLAUDE_CODE_JIT_POLICY_AFTER_STARTUPOther | Added in v2.1.299 | — |
CLAUDE_CODE_JSONL_TRANSCRIPTOther | Removed between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_JUNIPER_SUNDIALOther | Added in v2.1.218 | — |
CLAUDE_CODE_KB_COHESION_FIXESOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_LANTERN_PRISMOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_LARCH_CISTERNOther | Added between v2.1.215 and v2.1.217 | — |
CLAUDE_CODE_LAZY_ENV_GETTERSOther | Added in v2.1.299 | — |
CLAUDE_CODE_LEGACY_BUNDLEOther | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_LOOP_KEEPALIVEOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_LOOP_PERSISTENTOther | Added between v2.1.128 and v2.1.138 | Persist loop state across session boundaries. Loops don't die when the session restarts — they resume. Turns /loop from a within-session tool into a durable… |
CLAUDE_CODE_LUMINOUS_WHISTLEOther | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_MANAGED_CONFIG_PREFETCHOther | Added in v2.1.292 | Turns on a hedged prefetch of the organization's managed settings during startup, so the first managed-settings fetch runs earlier in the launch sequence.… |
CLAUDE_CODE_MANAGED_SETTINGS_PATHOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_MARKETPLACE_NAMEPlugins and skills | Added in v2.1.238 | — |
CLAUDE_CODE_MARKETPLACE_URLNetwork and proxy | Added in v2.1.238 | — |
CLAUDE_CODE_MARL_CORMORANTOther | Removed between v2.1.219 and v2.1.221 | — |
CLAUDE_CODE_MAX_CONCURRENT_SUBAGENTSAgents and subagents | Removed in v2.1.310 Documented | Ceiling on subagents running at once, default 20; when full Claude Code tells the model to stop and the user to raise this variable. Gated by… |
CLAUDE_CODE_MAX_CONTEXT_TOKENSContext and compaction | Added between v2.1.96 and v2.1.100 Documented | Sets an explicit ceiling on the context window size used during a session. Rather than relying on the model's default maximum, this variable lets operators cap… |
CLAUDE_CODE_MAX_EFFORT_REMINDERModels and thinking | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_MAX_MCP_DESCRIPTION_LENGTHMCP | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_MAX_OUTPUT_TOKENSContext and compaction | Present since v2.1.69 or earlier Documented | Maximum output tokens; validated per-model |
CLAUDE_CODE_MAX_RETRIESNetwork and proxy | Present since v2.1.69 or earlier Documented | Maximum API request retries |
CLAUDE_CODE_MAX_SUBAGENTS_PER_SESSIONAgents and subagents | Added between v2.1.143 and v2.1.212 Documented | Per-session ceiling on subagent spawns (default 200). When the cap is hit, Claude Code injects a prompt — "Subagent spawn limit reached. Complete the remaining… |
CLAUDE_CODE_MAX_SUBAGENT_SPAWN_DEPTHAgents and subagents | Removed between v2.1.245 and v2.1.247 Documented | Nesting-depth cap on delegation, default 1 — subagents no longer spawn their own subagents, and the team roster stays flat. Gated by tengu_hazel_trellis. First… |
CLAUDE_CODE_MAX_TOOL_USE_CONCURRENCYShell and tools | Present since v2.1.69 or earlier | Max concurrent tool executions; default 10 |
CLAUDE_CODE_MAX_TURNSOther | Added between v2.1.138 and v2.1.143 Documented | Hard cap on conversation turns. The single most important variable in this release for anyone running unattended agents. Set it to 50, 100, or whatever your… |
CLAUDE_CODE_MAX_WEB_SEARCHES_PER_SESSIONShell and tools | Added between v2.1.143 and v2.1.212 Documented | Per-session ceiling on WebSearch tool calls (default 200), gated by a web_search_session_cap. Its exhaustion string tells the model "this session has used its… |
CLAUDE_CODE_MCP_ALLOWLIST_ENVMCP | Added in v2.1.94 Documented | Specifies an allowlist of environment variables that MCP servers can access. MCP servers run as subprocesses and inherit the parent environment by default,… |
CLAUDE_CODE_MCP_ALWAYS_LOAD_JOIN_BEFORE_INPUTMCP | Added in v2.1.299 | — |
CLAUDE_CODE_MCP_APPS_HOSTMCP | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_MCP_AUTO_BACKGROUND_MSMCP | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_MCP_CONNECTOR_PREWAIT_MSNetwork and proxy | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_MCP_INSTR_DELTAMCP | Removed in v2.1.91 | Delta/incremental MCP instruction updates. Instead of sending full MCP server instructions every turn, this likely enables sending only changes — reducing… |
CLAUDE_CODE_MCP_MEMORY_CGROUPMCP | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_MCP_PREWAIT_SERVERSMCP | Added in v2.1.286 | — |
CLAUDE_CODE_MCP_PREWAIT_SERVERS_MSMCP | Added in v2.1.286 | — |
CLAUDE_CODE_MCP_SERVER_NAMEMCP | Added in v2.1.85 | Added in v2.1.85 to identify which MCP server a helper process was acting on behalf of. Removed after just two versions. |
CLAUDE_CODE_MCP_SERVER_URLNetwork and proxy | Added in v2.1.85 | The companion to MCP_SERVER_NAME, providing the server endpoint URL. Also removed. Together these formed a pair for routing MCP requests through a single… |
CLAUDE_CODE_MCP_SERVE_AUTH_TOKENAuthentication | Removed in v2.1.310 | — |
CLAUDE_CODE_MCP_SERVE_ENABLED_PLUGINSMCP | Added in v2.1.304 | — |
CLAUDE_CODE_MCP_SERVE_INTERFACE_MIN_VERSIONMCP | Added in v2.1.299 | — |
CLAUDE_CODE_MCP_SERVE_SETTINGSMCP | Added in v2.1.285 | — |
CLAUDE_CODE_MCP_SERVE_TOOL_OUTPUTMCP | Added in v2.1.287 | — |
CLAUDE_CODE_MCP_SERVE_WORKSPACE_ROOTMCP | Added between v2.1.301 and v2.1.303 | Used by claude mcp serve --transport http. Registers a workspace-root folder for the server; only a folder beneath the server's own is accepted, and a path… |
CLAUDE_CODE_MCP_STARTUP_WAIT_MSMCP | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_MCP_TOOL_IDLE_TIMEOUTNetwork and proxy | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_MEMORY_API_BASE_URLNetwork and proxy | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_CODE_MEMORY_API_TOKENAuthentication | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_CODE_MEMORY_PUSH_DELETE_MODEMemory and CLAUDE.md | Added between v2.1.143 and v2.1.212 | Controls how deletions propagate when memory is pushed upstream — a delete-mode knob for the memory subsystem that gained account- and organization-scoped sync… |
CLAUDE_CODE_MEMORY_SUBAGENT_APPENDAgents and subagents | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_MESSAGES_PROMPT_CACHE_TTLOther | Added in v2.1.300 | Set to 5m to force the messages prompt cache to a five-minute lifetime. It sits beside the existing CLAUDE_CODE_PROMPT_CACHE_TTL and… |
CLAUDE_CODE_MESSAGING_SOCKETOther | Added between v2.1.222 and v2.1.224 Documented | — |
CLAUDE_CODE_MESSAGING_TOKENAuthentication | Added in v2.1.228 Documented | Controls access to the local inbox for cross-session messages. A sender opens the socket named in CLAUDE_CODE_MESSAGING_SOCKET and sends this token first. If… |
CLAUDE_CODE_MID_CONVERSATION_SYSTEMOther | Removed between v2.1.143 and v2.1.212 | Inject a system message mid-conversation. Your harness can update Claude's constraints, inject new context, or shift behavioral guidelines without ending the… |
CLAUDE_CODE_MOCK_REMOTE_SETTINGSSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_MOCK_TRIALOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_MODEL_CAPABILITIESModels and thinking | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_MODEL_CATALOGModels and thinking | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_MODEL_CATALOG_URLNetwork and proxy | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_MORNING_BRIEF_PROMPTOther | Removed between v2.1.212 and v2.1.215 | — |
CLAUDE_CODE_NANKEEN_KESTRELOther | Added between v2.1.143 and v2.1.212 | Windows-only sandbox gate. The gate function returns false on any non-Windows OS, true if this variable is set, otherwise defers to the server gate… |
CLAUDE_CODE_NATIVE_CURSORTerminal and UI | Added between v2.1.128 and v2.1.138 Documented | Use native terminal cursor control. Extension of the terminal-native capabilities that came in with v2.1.113's binary launcher. If cursor positioning looks off… |
CLAUDE_CODE_NEW_INITOther | Added between v2.1.77 and v2.1.79 Documented | Toggles a refactored initialization path that reduces startup memory usage. The changelog explicitly highlights "~18MB" savings across all scenarios, which is… |
CLAUDE_CODE_NONBLOCKING_STDOUTOther | Added between v2.1.252 and v2.1.266 Documented | — |
CLAUDE_CODE_NONSTREAMING_TIMEOUT_RETRIESNetwork and proxy | Removed in v2.1.310 Documented | Caps how many times a timed-out non-streaming fallback request is re-sent. Added in v2.1.285. |
CLAUDE_CODE_NO_FLICKERTerminal and UI | Added between v2.1.87 and v2.1.88 Documented | Enables flicker-free alternate-screen rendering. The changelog[1] explicitly documents this as CLAUDE_CODE_NO_FLICKER=1. |
CLAUDE_CODE_NO_MODEL_FALLBACKModels and thinking | Added between v2.1.212 and v2.1.215 | When set, the availability chain collapses to [primary]: buildAvailabilityFallbackChain() returns only the model you selected, and a tripwire error fires if… |
CLAUDE_CODE_OAUTH_401_WAIT_MSAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_OAUTH_CLIENT_IDAuthentication | Present since v2.1.69 or earlier | Custom OAuth client ID |
CLAUDE_CODE_OAUTH_REFRESH_TOKENAuthentication | Present since v2.1.69 or earlier Documented | OAuth refresh token |
CLAUDE_CODE_OAUTH_SCOPESAuthentication | Present since v2.1.69 or earlier Documented | OAuth scopes for refresh token |
CLAUDE_CODE_OAUTH_TOKENAuthentication | Present since v2.1.69 or earlier Documented | Pre-configured OAuth access token |
CLAUDE_CODE_OAUTH_TOKEN_FILE_DESCRIPTORAuthentication | Present since v2.1.69 or earlier | File descriptor to read OAuth token from |
CLAUDE_CODE_OPUS_4_6_FAST_MODE_OVERRIDEModels and thinking | Added between v2.1.138 and v2.1.143 Documented | Pin Fast mode to Opus 4.6. Fast mode upgraded to Opus 4.7 by default in v2.1.142. If you're evaluating 4.7 or have a reproducibility requirement — benchmarks,… |
CLAUDE_CODE_ORGANIZATION_UUIDOther | Present since v2.1.69 or earlier | Organization UUID |
CLAUDE_CODE_OTEL_CONTENT_MAX_LENGTHTelemetry | Added between v2.1.212 and v2.1.215 Documented | Caps the length of content attributes on OpenTelemetry spans and logs; the truncation function takes the minimum of this value (default 60 KB) and the standard… |
CLAUDE_CODE_OTEL_DIAG_STDERRTelemetry | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_OTEL_FLUSH_TIMEOUT_MSTelemetry | Present since v2.1.69 or earlier Documented | OpenTelemetry flush timeout; default 5000ms |
CLAUDE_CODE_OTEL_HEADERS_HELPER_DEBOUNCE_MSTelemetry | Present since v2.1.69 or earlier Documented | Debounce for OTEL headers helper |
CLAUDE_CODE_OTEL_SHUTDOWN_TIMEOUT_MSTelemetry | Present since v2.1.69 or earlier Documented | OpenTelemetry shutdown timeout; default 2000ms |
CLAUDE_CODE_OVERLOADED_RETRY_BASE_DELAY_MSNetwork and proxy | Added in v2.1.292 Documented | Sets the base delay, in milliseconds, for the backoff when a request comes back overloaded (HTTP 529). The retry loop seeds its wait from this value on… |
CLAUDE_CODE_OVERLOADED_RETRY_MAX_DELAY_MSNetwork and proxy | Added in v2.1.296 Documented | Raises the ceiling on the backoff delay when retrying a request that returned a 529 overloaded response. It applies to the overloaded retry path specifically,… |
CLAUDE_CODE_OVERRIDE_DATETerminal and UI | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_OWNERSHIP_FRAMEOther | Removed between v2.1.215 and v2.1.217 | — |
CLAUDE_CODE_PACKAGE_MANAGER_AUTO_UPDATEOther | Added between v2.1.128 and v2.1.138 Documented | Control whether Claude Code auto-updates itself. If you manage Claude Code versions centrally (fleet policy, pinned version in a Dockerfile, corp registry),… |
CLAUDE_CODE_PARCHMENT_FERNOther | Removed in v2.1.285 | — |
CLAUDE_CODE_PARKED_PERMISSION_WAIT_MSPermissions and sandbox | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_PARKED_RUN_BEFORE_CLEAROther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_PARKED_STOP_RETIRESOther | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_PARSED_WILLOWOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_PERFETTO_TRACETelemetry | Present since v2.1.69 or earlier | Enable Perfetto trace output to file path (server-gated) |
CLAUDE_CODE_PERFETTO_WRITE_INTERVAL_STelemetry | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_PERFORCE_MODEOther | Added between v2.1.96 and v2.1.100 Documented | Activates Perforce VCS integration. The changelog[1] specifies: "when set, Edit/Write/NotebookEdit fail on read-only files with a p4 edit hint instead of… |
CLAUDE_CODE_PERSONAL_CONFIG_FIXOther | Added in v2.1.304 | — |
CLAUDE_CODE_PER_TURN_TIMINGOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_PEWTER_OWLOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_PEWTER_OWL_TOOLShell and tools | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_PLAN_ARTIFACTSOther | Removed between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_PLAN_MODE_INTERVIEW_PHASEOther | Removed between v2.1.143 and v2.1.212 | Enable interview phase in plan mode |
CLAUDE_CODE_PLAN_MODE_REQUIREDOther | Present since v2.1.69 or earlier | Require agents to use plan mode for all tasks |
CLAUDE_CODE_PLAN_V2_AGENT_COUNTAgents and subagents | Present since v2.1.69 or earlier | Number of agents in Plan v2 mode (1–10) |
CLAUDE_CODE_PLAN_V2_EXPLORE_AGENT_COUNTAgents and subagents | Present since v2.1.69 or earlier | Exploration agents in Plan v2 (1–10) |
CLAUDE_CODE_PLUGIN_ARCHIVE_URLNetwork and proxy | Added in v2.1.238 | — |
CLAUDE_CODE_PLUGIN_ATTRIBUTIONPlugins and skills | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_PLUGIN_BINARY_ASSETSPlugins and skills | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_PLUGIN_CACHE_DIRPlugins and skills | Removed in v2.1.310 Documented | Local cache directory for downloaded plugins |
CLAUDE_CODE_PLUGIN_DIRSPlugins and skills | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_PLUGIN_DIR_WATCHPlugins and skills | Removed between v2.1.307 and v2.1.309 Documented | — |
CLAUDE_CODE_PLUGIN_GIT_TIMEOUT_MSNetwork and proxy | Present since v2.1.69 or earlier Documented | Git clone timeout for plugin installation |
CLAUDE_CODE_PLUGIN_KEEP_MARKETPLACE_ON_FAILUREPlugins and skills | Added in v2.1.90 Documented | Preserves the local marketplace plugin cache when git pull fails. Source code shows that without this flag, a failed pull triggers a full delete-and-reclone of… |
CLAUDE_CODE_PLUGIN_NAMEPlugins and skills | Added in v2.1.238 | — |
CLAUDE_CODE_PLUGIN_PREFER_HTTPSPlugins and skills | Added between v2.1.138 and v2.1.143 Documented | Force HTTPS for plugin source resolution. If you're in a network environment where HTTP traffic is intercepted or plugins could be fetched without TLS, this… |
CLAUDE_CODE_PLUGIN_SEED_DIRPlugins and skills | Present since v2.1.69 or earlier Documented | Seed directory for pre-installed plugins |
CLAUDE_CODE_PLUGIN_USE_ZIP_CACHEPlugins and skills | Present since v2.1.69 or earlier | Use zip-based caching instead of git |
CLAUDE_CODE_POLICY_HELPER_PS1_PATHOther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_POLICY_HELPER_PSMODULEPATHOther | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_POLISHED_DEWDROPOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_POLL_EVENTSOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_POLL_EVENT_DECLARATIONSOther | Added in v2.1.287 | — |
CLAUDE_CODE_POST_FOR_SESSION_INGRESS_V2Sessions | Removed between v2.1.219 and v2.1.221 | Use POST-based session ingress v2 |
CLAUDE_CODE_POST_TURN_MEMORYMemory and CLAUDE.md | Removed in v2.1.290 | — |
CLAUDE_CODE_POST_TURN_MEMORY_CONFIGMemory and CLAUDE.md | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_POST_TURN_MEMORY_SYNCMemory and CLAUDE.md | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_POWERSHELL_RESPECT_EXECUTION_POLICYShell and tools | Added between v2.1.138 and v2.1.143 Documented | Restore PowerShell execution policy checks. v2.1.143 made bypass-policy the default to reduce the most common Windows friction. If your environment uses… |
CLAUDE_CODE_POWERUP_ONBOARDINGOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_PRINT_BG_WAIT_CEILING_MSSessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_PRINT_ENGINE_LOOPOther | Removed between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_PROACTIVEOther | Added in v2.1.128 | — |
CLAUDE_CODE_PROCESS_WRAPPEROther | Added between v2.1.143 and v2.1.212 Documented | Names an executable that Claude Code must launch itself through. When the CLI spawns a copy of itself — the background daemon, agent-view workers, subagents —… |
CLAUDE_CODE_PROFILE_QUERYDebugging | Added between v2.1.143 and v2.1.212 | Likely merged into general profiling |
CLAUDE_CODE_PROFILE_STARTUPDebugging | Present since v2.1.69 or earlier | Enable startup profiling; set to 1 |
CLAUDE_CODE_PROJECTS_SESSIONSessions | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_PROJECT_DIR_NAMEOther | Removed in v2.1.307 Documented | — |
CLAUDE_CODE_PROMPT_CACHE_TTLOther | Removed between v2.1.245 and v2.1.247 Documented | — |
CLAUDE_CODE_PROPAGATE_TRACEPARENTOther | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_PROVIDER_MANAGED_BY_HOSTTerminal and UI | Added between v2.1.79 and v2.1.83 Documented | Indicates that the API provider configuration is managed by the host application rather than by Claude Code itself. |
CLAUDE_CODE_PROXY_AUTHENTICATEAuthentication | Added between v2.1.108 and v2.1.114 | Carries the WWW-Authenticate challenge from the proxy into the helper. Enables challenge-response schemes by reading what the proxy actually asked for. |
CLAUDE_CODE_PROXY_AUTH_HELPER_TTL_MSAuthentication | Added between v2.1.108 and v2.1.114 | Cache TTL for helper-returned credentials. Parsed as integer milliseconds; zero or negative falls back to default. |
CLAUDE_CODE_PROXY_HOSTNetwork and proxy | Added between v2.1.108 and v2.1.114 | Proxy hostname, passed alongside the URL so helpers that route credentials by hostname don't need to re-parse. |
CLAUDE_CODE_PROXY_RESOLVES_HOSTSNetwork and proxy | Present since v2.1.69 or earlier Documented | Proxy handles DNS resolution (skip local DNS) |
CLAUDE_CODE_PROXY_URLNetwork and proxy | Added between v2.1.108 and v2.1.114 | Full proxy URL, injected into the helper subprocess's environment. Claude-namespaced because the helper protocol is Claude-specific and must not collide with… |
CLAUDE_CODE_PWSH_PARSE_TIMEOUT_MSNetwork and proxy | Added in v2.1.85 | Sets the timeout for PowerShell command parsing on Windows. The PowerShell tool shipped as a preview in v2.1.84 with CLAUDE_CODE_USE_POWERSHELL_TOOL — this… |
CLAUDE_CODE_QUESTION_EXTENDEDOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_QUESTION_OPTIONAL_DESCRIPTIONSOther | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_QUESTION_PREVIEW_FORMATOther | Present since v2.1.69 or earlier | Format for permission question previews |
CLAUDE_CODE_RATE_LIMIT_TIEROther | Added between v2.1.114 and v2.1.117 | Rate-limit bucket for the current session, independent of subscription type. Enterprise customers may have custom limits that differ from their plan defaults —… |
CLAUDE_CODE_RC_PERMISSION_NUDGEPermissions and sandbox | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_REFUSAL_FALLBACK_CATCH_ALLOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_RELAUNCH_HOME_TRUSTOther | Added in v2.1.284 | — |
CLAUDE_CODE_RELAUNCH_PROACTIVITY_BASELINEOther | Added in v2.1.290 | — |
CLAUDE_CODE_RELAUNCH_PROACTIVITY_EVER_ONOther | Removed in v2.1.310 | — |
CLAUDE_CODE_RELAUNCH_PROACTIVITY_LEVELOther | Added in v2.1.290 | — |
CLAUDE_CODE_RELAUNCH_TERMINAL_SIZETerminal and UI | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_REMOTESessions | Present since v2.1.69 or earlier Documented | Indicates running in remote/server mode |
CLAUDE_CODE_REMOTE_ENVIRONMENT_TYPESessions | Present since v2.1.69 or earlier | Remote environment type sent in telemetry |
CLAUDE_CODE_REMOTE_HERMETIC_MODESessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_REMOTE_MCP_CONFIGMCP | Added in v2.1.299 | — |
CLAUDE_CODE_REMOTE_MEMORY_DIRMemory and CLAUDE.md | Present since v2.1.69 or earlier | Memory directory for remote sessions |
CLAUDE_CODE_REMOTE_RAW_EVENTS_FILESessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_REMOTE_SDK_URLNetwork and proxy | Added in v2.1.290 | — |
CLAUDE_CODE_REMOTE_SEND_KEEPALIVESSessions | Present since v2.1.69 or earlier | Send keepalive pings in remote mode |
CLAUDE_CODE_REMOTE_SESSION_IDSessions | Present since v2.1.69 or earlier Documented | Remote session identifier |
CLAUDE_CODE_REMOTE_SESSION_ORIGINSessions | Added between v2.1.215 and v2.1.217 | Provenance tag for cloud/remote sessions, checked against the value "review". First shipped v2.1.217; undocumented. |
CLAUDE_CODE_REMOTE_SESSION_UUIDSessions | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_CODE_REMOTE_SETTINGS_PATHSessions | Removed in v2.1.310 | — |
CLAUDE_CODE_REMOTE_SETTINGS_POLL_MSSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_REMOTE_TOOLS_ADOPT_MCPMCP | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_REMOTE_TOOLS_ASK_SEATSShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_REMOTE_TOOLS_CALLER_SESSIONS_MAXShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_REMOTE_TOOLS_FORWARDShell and tools | Removed in v2.1.310 | — |
CLAUDE_CODE_REMOTE_TOOLS_HOST_ALLOWS_UNATTENDEDShell and tools | Added in v2.1.290 | — |
CLAUDE_CODE_REMOTE_TOOLS_JUMP_QUEUEShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_REMOTE_TOOLS_PIN_STORED_LOGINShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_REMOTE_TOOLS_POLICYShell and tools | Added between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_REMOTE_TOOLS_SERVEShell and tools | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_REMOTE_TOOLS_SESSION_CHANNELShell and tools | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_REMOTE_TOOLS_SPECULATIVE_CLASSIFIERShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_REMOVE_PROMPT_STRINGSOther | Added in v2.1.290 | — |
CLAUDE_CODE_REPLOther | Added between v2.1.87 and v2.1.88 | Boolean toggle for the new native REPL path introduced by v2.1.113's native-binary launcher. Forces on or off regardless of entrypoint detection — the… |
CLAUDE_CODE_REPORT_FINDINGSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_REPO_CHECKOUTSOther | Added between v2.1.104 and v2.1.107 | Specifies a directory path (or paths) where Claude Code should create and manage git worktree checkouts. By default, worktrees land in a temporary location… |
CLAUDE_CODE_RESTRICTEDPermissions and sandbox | Added between v2.1.247 and v2.1.252 Documented | — |
CLAUDE_CODE_RESTRICT_PERSONAL_CONFIGOther | Added in v2.1.295 | Limits what a session's own Claude Code files may do. With it set, a user's own agents cannot define their own MCP servers or widen their permission mode, the… |
CLAUDE_CODE_RESULT_NONCEOther | Added in v2.1.285 | — |
CLAUDE_CODE_RESUME_FROM_SESSIONSessions | Added between v2.1.104 and v2.1.107 | Instructs Claude Code to bootstrap a new session's context from an existing session ID. Rather than starting fresh, the new session loads key context —… |
CLAUDE_CODE_RESUME_INTERRUPTED_TURNSessions | Present since v2.1.69 or earlier Documented | Resume an interrupted agent turn |
CLAUDE_CODE_RESUME_INTERRUPTED_TURN_MAX_AGE_MSSessions | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_RESUME_PROMPTSessions | Added between v2.1.138 and v2.1.143 Documented | Set the prompt injected when resuming a session. If you build on top of Claude Code's resume capability and want Claude to get oriented differently on re-entry… |
CLAUDE_CODE_RESUME_PROMPT00Sessions | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_RESUME_REASONSessions | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_RESUME_SESSIONSTART_HOOKS_WAIT_MSSessions | Added in v2.1.296 | — |
CLAUDE_CODE_RESUME_SHOWS_CUT_OFF_CALLSSessions | Added between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_RESUME_SOURCE_ALIVESessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_RESUME_THRESHOLD_MINUTESSessions | Removed between v2.1.245 and v2.1.247 | Sets the time window (in minutes) during which a session is eligible for automatic resume. Claude Code already supports --resume for continuing sessions, and… |
CLAUDE_CODE_RESUME_TOKEN_THRESHOLDAuthentication | Added between v2.1.88 and v2.1.89 | Sets the token count threshold for session resume eligibility. Complementing the time-based threshold above, this adds a context-size dimension: if a session's… |
CLAUDE_CODE_RESUME_TOLERATES_CONTEXT_APPENDSContext and compaction | Removed between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_RESUME_TOLERATES_CONTEXT_SEEDSContext and compaction | Added in v2.1.290 | — |
CLAUDE_CODE_RETIRE_UNANSWERED_PARKED_PERMISSIONPermissions and sandbox | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_RETRY_WATCHDOGNetwork and proxy | Added between v2.1.114 and v2.1.117 Documented | Tunes the retry watchdog that detects API calls silently looping without progress. v2.1.123 fixed an OAuth 401 retry loop when… |
CLAUDE_CODE_RETRY_WATCHDOG_MAX_USAGE_LIMIT_WAIT_MSNetwork and proxy | Added in v2.1.301 | Bounds how long unattended retry mode (CLAUDE_CODE_RETRY_WATCHDOG) waits for a usage-limit reset. When a 429 response's reset is farther out than this budget,… |
CLAUDE_CODE_RETRY_WATCHDOG_MAX_WAIT_MSNetwork and proxy | Added in v2.1.295 Documented | Caps the total time unattended retry mode (CLAUDE_CODE_RETRY_WATCHDOG) waits through 429 and 529 responses. Once the elapsed wait passes the cap, the request… |
CLAUDE_CODE_RETRY_WATCHDOG_SCOPENetwork and proxy | — | Read alongside CLAUDE_CODE_RETRY_WATCHDOG. With the watchdog on, the guarded branch runs only when this is not set to capacity; setting it to capacity turns… |
CLAUDE_CODE_RETRY_WATCHDOG_SCOPE1Network and proxy | Added in v2.1.310 | — |
CLAUDE_CODE_RETRY_WATCHDOG_USAGE_LIMIT_RECHECK_MSNetwork and proxy | Added in v2.1.305 Documented | Governs how unattended retry mode (CLAUDE_CODE_RETRY_WATCHDOG) rechecks a usage limit that was lifted before its reset, so a headless run can resume once the… |
CLAUDE_CODE_RIPPLING_TULIPOther | Added in v2.1.290 | — |
CLAUDE_CODE_RUSTLING_PIXELOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_SABLE_THRUSHOther | Removed between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_SAFE_MODEOther | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_SANDBOXEDPermissions and sandbox | Added in v2.1.94 | Indicates or enforces that Claude Code is running in a sandboxed environment. The v2.1.92 changelog[1] restored the apply-seccomp helper for Linux sandbox in… |
CLAUDE_CODE_SANDBOX_LEAVE_DENIES_TO_SRT_WINPermissions and sandbox | Added in v2.1.299 | — |
CLAUDE_CODE_SANDBOX_LEAVE_PARENT_FOLDERS_ALONEPermissions and sandbox | Added in v2.1.299 | — |
CLAUDE_CODE_SAVE_HOOK_ADDITIONAL_CONTEXTContext and compaction | Removed between v2.1.96 and v2.1.100 | Extra context passed to save hooks |
CLAUDE_CODE_SCRIPT_CAPSOther | Added between v2.1.96 and v2.1.100 Documented | Limits per-session script invocations. The changelog[1] pairs this with subprocess sandboxing via PID namespace isolation on Linux (when… |
CLAUDE_CODE_SCROLL_SPEEDTerminal and UI | Removed in v2.1.310 Documented | Controls the scroll speed within the terminal UI. Default scroll behavior in terminal applications is typically one line per scroll event, which can feel… |
CLAUDE_CODE_SCROLL_SPEEDITerminal and UI | Removed in v2.1.228 | — |
CLAUDE_CODE_SCROLL_SPEEDI30Terminal and UI | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_SDK_HAS_HOST_AUTH_REFRESHAuthentication | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SDK_HAS_OAUTH_REFRESHAuthentication | Added between v2.1.100 and v2.1.104 | Signals to the Claude Code runtime that the SDK caller has already provided an OAuth refresh token. |
CLAUDE_CODE_SDK_READS_SESSION_STATESessions | Added in v2.1.284 | — |
CLAUDE_CODE_SDK_READS_STARTUP_MARKSOther | Added in v2.1.304 | — |
CLAUDE_CODE_SEARCH_HINTS_IN_LISTOther | Removed between v2.1.87 and v2.1.88 | Controlled whether search hints appeared in list views. The feature was probably either made default or removed as the UI evolved. |
CLAUDE_CODE_SENDMESSAGE_HANDBACKOther | Removed between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_SEND_FEEDBACKOther | Added between v2.1.143 and v2.1.212 Documented | Kill switch for the new /bug feedback relay. The gate function bails if DISABLE_FEEDBACK_COMMAND or DISABLE_BUG_COMMAND is set, requires an… |
CLAUDE_CODE_SESSIONEND_HOOKS_TIMEOUT_MSNetwork and proxy | Added between v2.1.77 and v2.1.79 Documented | Set the timeout in milliseconds for hooks that run when a Claude Code session ends. Session-end hooks (like SessionEnd in the hooks config) run cleanup scripts… |
CLAUDE_CODE_SESSION_ACCESS_TOKENAuthentication | Removed in v2.1.310 | Session-scoped access token |
CLAUDE_CODE_SESSION_ATTENDEDSessions | Added in v2.1.310 | — |
CLAUDE_CODE_SESSION_IDSessions | Added between v2.1.118 and v2.1.123 Documented | Stable identifier for the current session, passed into subprocess environments. Lets subprocess tools — hooks, MCP servers, custom scripts — correlate their… |
CLAUDE_CODE_SESSION_KINDSessions | Added between v2.1.118 and v2.1.123 | Classifies the session: interactive, SDK/headless, subagent, background, or Remote Control. Hooks can branch on kind — a hook that opens a browser link makes… |
CLAUDE_CODE_SESSION_LOGSessions | Added between v2.1.118 and v2.1.123 | Path to the session's transcript file, surfaced to subprocesses. Lets hooks and post-processing scripts find the transcript without traversing ~/.claude/ or… |
CLAUDE_CODE_SESSION_NAMESessions | Added between v2.1.118 and v2.1.123 | Human-readable session name backing the v2.1.121 terminal tab title feature. Hooks and status-line integrations can read it without querying the CLI. |
CLAUDE_CODE_SESSION_ORIGINSessions | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_SESSION_START_ANNOUNCEMENTS_BEFORE_PROMPTSessions | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_SHELLShell and tools | Present since v2.1.69 or earlier Documented | Override shell for Bash tool (must be bash or zsh) |
CLAUDE_CODE_SHELL_LAUNCHER_SCRIPTShell and tools | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_SHELL_PREFIXShell and tools | Present since v2.1.69 or earlier Documented | Prefix command for shell execution |
CLAUDE_CODE_SHELL_PREFIXI50Shell and tools | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_SILENT_TURN_REMINDEROther | Removed in v2.1.310 | — |
CLAUDE_CODE_SILENT_TURN_REMINDER_SECONDSOther | Removed in v2.1.310 | — |
CLAUDE_CODE_SILENT_TURN_REMINDER_TEXTOther | Added in v2.1.238 | — |
CLAUDE_CODE_SILENT_TURN_REMINDER_TURNSOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_SIMPLEOther | Present since v2.1.69 or earlier Documented | Simplified mode; disables CLAUDE.md and attachments (renamed from CLAUDE_CODE_SIMPLETON) |
CLAUDE_CODE_SIMPLETONOther | — | Renamed to CLAUDE_CODE_SIMPLE |
CLAUDE_CODE_SIMPLE_SYSTEM_PROMPTOther | Added between v2.1.114 and v2.1.117 Documented | Switches to a reduced system prompt, stripping out the non-essential guidance sections that bulk up the default prompt. Useful in latency-sensitive or… |
CLAUDE_CODE_SIMULATE_PROXY_USAGENetwork and proxy | Removed in v2.1.310 | Simulates proxy-based API routing without an actual proxy. This is a testing tool — it lets developers verify that their Claude Code configuration behaves… |
CLAUDE_CODE_SKILL_ATTRIBUTIONPlugins and skills | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_SKILL_DESCRIPTIONPlugins and skills | Removed between v2.1.212 and v2.1.215 | — |
CLAUDE_CODE_SKILL_DESC_REFRAMEPlugins and skills | Removed between v2.1.215 and v2.1.217 | — |
CLAUDE_CODE_SKILL_NAMEPlugins and skills | Removed between v2.1.247 and v2.1.252 | — |
CLAUDE_CODE_SKILL_PROPOSALSPlugins and skills | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_SKIP_ANTHROPIC_AWS_AUTHCloud providers | Added in v2.1.90 Documented | Skips credential resolution for the Anthropic AWS provider. Source code shows two effects: (1) passes skipAuth: true to the AnthropicAws client constructor,… |
CLAUDE_CODE_SKIP_ANTHROPIC_GOOGLE_CLOUD_AUTHCloud providers | Added between v2.1.212 and v2.1.215 | The skip-auth companion to the toggle above, grouped in the auth-bypass list with SKIP_BEDROCK_AUTH, SKIP_VERTEX_AUTH, SKIP_FOUNDRY_AUTH,… |
CLAUDE_CODE_SKIP_AWS_CRED_CACHECloud providers | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_SKIP_BEDROCK_AUTHCloud providers | Present since v2.1.69 or earlier Documented | Skip Bedrock authentication |
CLAUDE_CODE_SKIP_FAST_MODE_NETWORK_ERRORSModels and thinking | Added between v2.1.77 and v2.1.79 Documented | Controls whether Claude Code suppresses or bypasses network errors that occur specifically in fast mode. Fast mode uses the same Opus 4.6 model with faster… |
CLAUDE_CODE_SKIP_FAST_MODE_ORG_CHECKModels and thinking | Removed in v2.1.310 Documented | Disables the organization-level eligibility check for fast mode. Fast mode (toggled via /fast) normally verifies that the user's organization supports it. |
CLAUDE_CODE_SKIP_FOUNDRY_AUTHCloud providers | Present since v2.1.69 or earlier Documented | Skip Foundry authentication |
CLAUDE_CODE_SKIP_HFI_VERSION_CHECKFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SKIP_MANTLE_AUTHCloud providers | Added in v2.1.94 Documented | Skips Mantle authentication. This is the escape hatch for environments where Mantle is enabled at the org level but a specific workflow needs direct API access… |
CLAUDE_CODE_SKIP_MODEL_ACCESS_MEMORYModels and thinking | Added in v2.1.285 Documented | — |
CLAUDE_CODE_SKIP_PLUGIN_LOCAL_MCP_SERVERSMCP | Added in v2.1.304 | — |
CLAUDE_CODE_SKIP_PLUGIN_MCP_BUNDLESMCP | Added in v2.1.304 | — |
CLAUDE_CODE_SKIP_PLUGIN_MCP_SERVERSMCP | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SKIP_PLUGIN_MCP_SERVERS_EXCEPTMCP | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SKIP_PRECOMPACT_LOADContext and compaction | — | Optimize large session file loading |
CLAUDE_CODE_SKIP_PROJECT_BACKFILLFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SKIP_PROJECT_BACKFILL_LFeature toggles | Removed between v2.1.224 and v2.1.227 | — |
CLAUDE_CODE_SKIP_PROMPT_HISTORYFeature toggles | Present since v2.1.69 or earlier Documented | Disable prompt history saving |
CLAUDE_CODE_SKIP_REPO_UPLOADFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SKIP_VERTEX_AUTHCloud providers | Present since v2.1.69 or earlier Documented | Skip Vertex AI authentication |
CLAUDE_CODE_SLACK_TAG_TOKENAuthentication | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_SLEEPY_SNOWFLAKEOther | Added in v2.1.284 | — |
CLAUDE_CODE_SLEEP_COMPACTContext and compaction | Added in v2.1.295 | — |
CLAUDE_CODE_SLEEP_COMPACT_AFTER_MSContext and compaction | Added in v2.1.296 | — |
CLAUDE_CODE_SLOW_OPERATION_THRESHOLD_MSOther | Present since v2.1.69 or earlier | Threshold for slow filesystem operation warnings |
CLAUDE_CODE_SNAPPY_PELICANOther | Added in v2.1.296 | — |
CLAUDE_CODE_SPAWNED_BY_SERVEROther | Present since v2.1.69 or earlier | Was used to indicate a server-spawned process. Added in v2.1.69's remote/server mode batch. Removed after just one version — likely internalized or replaced by… |
CLAUDE_CODE_SPAWN_TIMESTAMP_MSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SQUISHY_NEWTOther | Removed in v2.1.301 | — |
CLAUDE_CODE_SSE_PORTOther | Removed in v2.1.310 | Server-Sent Events port |
CLAUDE_CODE_STALL_TIMEOUT_MS_FOR_TESTINGNetwork and proxy | Removed in v2.1.310 | — |
CLAUDE_CODE_STARTUP_FAILURE_RESULTSOther | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_STELLAR_DRIFTOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_STOP_HOOK_BLOCK_CAPOther | Added between v2.1.138 and v2.1.143 Documented | Cap how long a stop hook can block session termination. If you've ever hit Ctrl+C and had Claude Code hang before actually closing — this is why, and this is… |
CLAUDE_CODE_STREAMED_BUMBLEBEENetwork and proxy | Added in v2.1.290 | — |
CLAUDE_CODE_STREAMED_BUMBLEBEE_TEXTNetwork and proxy | Added in v2.1.290 | — |
CLAUDE_CODE_STREAMING_TEXTNetwork and proxy | Removed between v2.1.73 and v2.1.76 | Likely controlled an experimental streaming text mode that has now graduated to being the default behavior. v2.1.78 introduced line-by-line response streaming… |
CLAUDE_CODE_STRICT_INLINE_SHELL_RM_PROMPTShell and tools | Added in v2.1.299 | Set to 1 to keep prompting on a run-time or inline rm in a shell -c script Claude Code cannot read. Left unset, scripts that do not visibly run rm no longer… |
CLAUDE_CODE_SUBAGENT_CACHE_EVICTAgents and subagents | Removed in v2.1.310 | — |
CLAUDE_CODE_SUBAGENT_CONFIG_WARNINGAgents and subagents | Added in v2.1.295 | — |
CLAUDE_CODE_SUBAGENT_HISTORYAgents and subagents | Removed in v2.1.310 | Gates a subagent history view; when unset the view falls back to the tengu_rustling_crescent feature gate, which is off by default. Present in v2.1.307, with… |
CLAUDE_CODE_SUBAGENT_MODELAgents and subagents | Present since v2.1.69 or earlier Documented | Force a specific model for sub-agent operations |
CLAUDE_CODE_SUBAGENT_MODELUAgents and subagents | — | The trailing-U variant flagged as a likely typo in v2.1.84 has been removed. CLAUDE_CODE_SUBAGENT_MODEL (without the U) remains. Clean housekeeping. |
CLAUDE_CODE_SUBAGENT_MODEL_FORCEAgents and subagents | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_SUBAGENT_PROMPT_CACHE_TTLAgents and subagents | Added between v2.1.241 and v2.1.245 Documented | — |
CLAUDE_CODE_SUBAGENT_PROMPT_SNAPSHOTAgents and subagents | Removed in v2.1.310 | — |
CLAUDE_CODE_SUBPROCESS_ENV_SCRUBPermissions and sandbox | Added between v2.1.77 and v2.1.79 Documented | When set to 1, strips Anthropic and cloud provider credentials from subprocess environments — the Bash tool, hooks, and MCP stdio servers. The changelog… |
CLAUDE_CODE_SUBSCRIPTION_TYPEOther | Added between v2.1.114 and v2.1.117 | Current subscription plan identifier. Lets the process branch on tier without an API call — used by v2.1.118's unified /usage to render plan-specific limits… |
CLAUDE_CODE_SUPERVISEDOther | Added between v2.1.138 and v2.1.143 | Mark a session as supervised — a human is watching. In supervised mode Claude is more likely to surface decisions for human confirmation rather than resolving… |
CLAUDE_CODE_SUPPRESS_SESSION_ATTRIBUTIONSessions | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SYNC_PLUGINSPlugins and skills | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SYNC_PLUGINSI3Plugins and skills | Removed in v2.1.228 | — |
CLAUDE_CODE_SYNC_PLUGINS_BUFFERED_DOWNLOADPlugins and skills | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SYNC_PLUGINS_DOWNLOAD_CONCURRENCYPlugins and skills | Added between v2.1.307 and v2.1.309 | — |
CLAUDE_CODE_SYNC_PLUGINS_DOWNLOAD_STALL_MSPlugins and skills | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SYNC_PLUGINS_INSTALL_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SYNC_PLUGINS_MCP_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_SYNC_PLUGIN_INSTALLPlugins and skills | Present since v2.1.69 or earlier Documented | Install plugins synchronously (block until done) |
CLAUDE_CODE_SYNC_PLUGIN_INSTALL_TIMEOUT_MSNetwork and proxy | Present since v2.1.69 or earlier Documented | Timeout for synchronous plugin install |
CLAUDE_CODE_SYNC_REUSE_WITHIN_MSOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_SYNC_SESSION_REFSSessions | Added between v2.1.143 and v2.1.212 | Enables syncing of session references in remote and child sessions. The gate function is true only when this variable is truthy and a CLAUDE_CODE_SESSION_ID is… |
CLAUDE_CODE_SYNC_SKILLSPlugins and skills | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_SYNC_SKILLS_INSTALL_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_SYNC_SKILLS_WAIT_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_SYNTAX_HIGHLIGHTOther | Removed in v2.1.286 Documented | Disable syntax highlighting when set to false |
CLAUDE_CODE_SYSTEM_PROMPT_GB_FEATUREOther | Added between v2.1.108 and v2.1.114 | Names a GrowthBook feature flag whose value overrides the system prompt — but only when CLAUDE_CODE_REMOTE is set. Anthropic can A/B-test remote-session… |
CLAUDE_CODE_TAGSOther | Present since v2.1.69 or earlier | Custom tags for telemetry events |
CLAUDE_CODE_TAG_ISMETA_MESSAGESOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TASK_LIST_IDOther | Removed in v2.1.310 Documented | Task list ID for agent coordination |
CLAUDE_CODE_TEAMMATE_COMMANDAgents and subagents | Present since v2.1.69 or earlier | Command for teammate/cowork functionality |
CLAUDE_CODE_TEAM_ONBOARDINGAgents and subagents | Removed between v2.1.143 and v2.1.212 | Replaced by newer onboarding paths (CLAUDE_CODE_POWERUP_ONBOARDING, /doctor's CLAUDE.md-trimming check). |
CLAUDE_CODE_TEAM_TEARDOWN_PARK_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TEE_SDK_STDOUTOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TERMINAL_MCP_TOOLSMCP | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TERMINAL_RECORDINGTerminal and UI | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TEST_ALLOW_REAL_NETWORKOther | Added between v2.1.238 and v2.1.241 | — |
CLAUDE_CODE_TEST_FIXTURES_ROOTOther | Present since v2.1.69 or earlier | Root directory for test fixtures |
CLAUDE_CODE_TEST_FORCE_DENYFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TEST_NO_GIT_BASHShell and tools | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TEST_NO_PWSHOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TETHER_LIVEOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_THINKING_DISPLAY_UPDATESModels and thinking | Added between v2.1.238 and v2.1.241 | Overrides whether Claude's in-progress thinking and connector text render during a turn. When set it takes precedence over the thinking_display_updates dynamic… |
CLAUDE_CODE_THISTLE_GREBEOther | Added between v2.1.215 and v2.1.217 | — |
CLAUDE_CODE_THRIFTY_SONICOther | Added in v2.1.222 | — |
CLAUDE_CODE_TICKLISH_WHISPEROther | Removed in v2.1.310 | — |
CLAUDE_CODE_TICKLISH_WHISPER_TIMEOUT_MSNetwork and proxy | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_TMPDIROther | Present since v2.1.69 or earlier Documented | Temp directory for operations |
CLAUDE_CODE_TMUX_PREFIXTerminal and UI | Present since v2.1.69 or earlier | Tmux prefix key shown in detach instructions |
CLAUDE_CODE_TMUX_PREFIX_CONFLICTSTerminal and UI | Present since v2.1.69 or earlier | Show prefix twice when key conflicts in tmux |
CLAUDE_CODE_TMUX_SESSIONTerminal and UI | Present since v2.1.69 or earlier | Tmux session name shown in UI header |
CLAUDE_CODE_TMUX_TRUECOLORTerminal and UI | Added between v2.1.79 and v2.1.83 Documented | Controls truecolor (24-bit) rendering when running inside tmux. Tmux has historically been tricky with truecolor support — it requires both the terminal… |
CLAUDE_CODE_TOASTY_THIMBLEOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_TODO_REMINDER_MODEOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TOOL_MEMORY_CGROUP_EXCLUDEShell and tools | Added between v2.1.245 and v2.1.247 Documented | — |
CLAUDE_CODE_TOOL_MEMORY_LIMITShell and tools | Added between v2.1.229 and v2.1.234 Documented | — |
CLAUDE_CODE_TOOL_USE_IDShell and tools | Added between v2.1.266 and v2.1.269 | — |
CLAUDE_CODE_TOTAL_TOKENS_REMINDERContext and compaction | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TOTAL_TOKENS_REMINDER_AFTER_USER_TURNContext and compaction | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TOTAL_TOKENS_REMINDER_BUDGETContext and compaction | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TRANSCRIPT_LOCAL_GCOther | Added between v2.1.215 and v2.1.217 Documented | Toggles local garbage-collection of on-disk session transcripts, backed by tengu_transcript_local_gc. First shipped v2.1.217; undocumented. |
CLAUDE_CODE_TRANSCRIPT_SLIM_TOOL_RESULTSShell and tools | Added in v2.1.310 | — |
CLAUDE_CODE_TRIGGER_IDOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_TUI_JUST_SWITCHEDOther | Added between v2.1.108 and v2.1.114 | Set to "fullscreen" immediately after /tui fullscreen. The next render reads it to show a one-time confirmation hint, then clears the flag. |
CLAUDE_CODE_TUI_TRIALOther | Added between v2.1.234 and v2.1.237 | — |
CLAUDE_CODE_TURN_UPDATESOther | Added in v2.1.229 | — |
CLAUDE_CODE_TWO_STAGE_CLASSIFIEROther | Added between v2.1.70 and v2.1.72 | Added in v2.1.72 as an opt-in flag for two-stage intent classification. Its removal after just two versions suggests the feature graduated out of flag-gating —… |
CLAUDE_CODE_ULTRAREVIEW_PREFLIGHT_FIXTUREOther | Added between v2.1.104 and v2.1.107 | Points to a test fixture file used during the preflight phase of UltraReview — Claude Code's automated PR review pipeline. In test and CI environments, this… |
CLAUDE_CODE_ULTRAREVIEW_PREFLIGHT_FIXTUREA2Other | Removed between v2.1.224 and v2.1.227 | — |
CLAUDE_CODE_ULTRAREVIEW_PREFLIGHT_FIXTUREB0Other | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_ULTRAREVIEW_QUOTA_FIXTUREOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_CODE_USER_DIALOG_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 Documented | — |
CLAUDE_CODE_USER_EMAILOther | Present since v2.1.69 or earlier | Pre-configured user email |
CLAUDE_CODE_USE_ANTHROPIC_AWSCloud providers | Added in v2.1.90 Documented | Selects "Claude Platform on AWS" as the API provider. Source code confirms this is a distinct provider alongside Bedrock, Vertex, and Foundry — the provider… |
CLAUDE_CODE_USE_ANTHROPIC_GOOGLE_CLOUDCloud providers | Added between v2.1.212 and v2.1.215 | A new provider-backend toggle sitting in Claude Code's exact provider family — beside CLAUDE_CODE_USE_BEDROCK, USE_VERTEX, USE_FOUNDRY, USE_ANTHROPIC_AWS,… |
CLAUDE_CODE_USE_BEDROCKCloud providers | Present since v2.1.69 or earlier Documented | Use Amazon Bedrock as backend |
CLAUDE_CODE_USE_CCR_V2Other | Present since v2.1.69 or earlier | Use Claude Code Router v2 for cowork sessions |
CLAUDE_CODE_USE_COWORK_PLUGINSPlugins and skills | Present since v2.1.69 or earlier | Use cowork_plugins directory instead of default |
CLAUDE_CODE_USE_FOUNDRYCloud providers | Present since v2.1.69 or earlier Documented | Use Anthropic Foundry as backend |
CLAUDE_CODE_USE_GATEWAYOther | Added between v2.1.143 and v2.1.212 | Routes traffic through an Anthropic-operated gateway (with loopback and log-level tuning). Centralized model access for managed fleets, behind the v2.1.206… |
CLAUDE_CODE_USE_MANTLECloud providers | Added in v2.1.94 Documented | Activates Mantle-based authentication for Amazon Bedrock. The changelog[1] describes this as "integrated Amazon Bedrock support via Mantle" with… |
CLAUDE_CODE_USE_NATIVE_FILE_SEARCHOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_USE_POWERSHELL_TOOLShell and tools | Added between v2.1.79 and v2.1.83 Documented | Enables a PowerShell-specific tool variant for Windows environments. This suggests the team is building first-class PowerShell support rather than routing… |
CLAUDE_CODE_USE_VERTEXCloud providers | Present since v2.1.69 or earlier Documented | Use Google Vertex AI as backend |
CLAUDE_CODE_VERIFY_PROMPTOther | Removed between v2.1.143 and v2.1.212 | The verify flow was reworked; the standalone prompt override no longer maps to how verification runs. |
CLAUDE_CODE_VERSIONOther | Added between v2.1.128 and v2.1.138 | Exposes the CLI version to subprocesses, hooks, and MCP servers. Your hooks and MCP tools can now read CLAUDE_CODE_VERSION directly — gate behavior on minimum… |
CLAUDE_CODE_VOICE_FORWARD_INTERIMS_TYPEDOther | Added between v2.1.138 and v2.1.143 | Stream interim voice transcription results as you speak rather than waiting for the final transcript. |
CLAUDE_CODE_WALNUT_SPIREOther | Removed between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_WALNUT_SPIREIOOther | Removed in v2.1.222 | — |
CLAUDE_CODE_WARN_DISK_FREE_GIBOther | Added in v2.1.304 Documented | — |
CLAUDE_CODE_WARN_MEMORY_FREE_GIBMemory and CLAUDE.md | — Documented | — |
CLAUDE_CODE_WEBFETCH_CACHE_TTL_MSShell and tools | Added between v2.1.229 and v2.1.234 Documented | — |
CLAUDE_CODE_WEBFETCH_DEADLINE_MSShell and tools | Removed in v2.1.310 Documented | — |
CLAUDE_CODE_WEBFETCH_USE_CCR_PROXYNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_WEBSEARCH_CITATIONSShell and tools | Added in v2.1.295 | Returns web-search results as structured citation blocks carrying source URLs instead of ending the answer with a plain Sources: link list. In a… |
CLAUDE_CODE_WEBSEARCH_USE_CCR_PROXYNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_WEBSOCKET_AUTH_FILE_DESCRIPTORAuthentication | Present since v2.1.69 or earlier | File descriptor for WebSocket credentials |
CLAUDE_CODE_WEB_FETCH_AGENTAgents and subagents | Added between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_WEB_SEARCH_FAST_ARGShell and tools | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_CODE_WEB_SEARCH_REFILLS_PER_HOURShell and tools | Added in v2.1.290 Documented | Sets how many web-search budget refills accrue per hour, overriding the value the feature gate serves. It accepts 0 to 3600 and defaults to 100 when unset; the… |
CLAUDE_CODE_WHIMSICAL_ELEPHANTOther | Added in v2.1.284 | — |
CLAUDE_CODE_WILLOW_TERNOther | Added between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_WISE_COMETOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_CODE_WITTY_DEWDROPOther | Added in v2.1.307 | — |
CLAUDE_CODE_WORKER_CHECKIN_SCHEDULEOther | Added between v2.1.269 and v2.1.283 Documented | — |
CLAUDE_CODE_WORKER_EPOCHOther | Present since v2.1.69 or earlier | Worker epoch for versioning internal state |
CLAUDE_CODE_WORKER_EPOCHIF0Other | Removed between v2.1.229 and v2.1.234 | — |
CLAUDE_CODE_WORKFLOWSAgents and subagents | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_WORKFLOW_LAUNCH_SHA256Agents and subagents | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_WORKFLOW_MAX_CONCURRENT_AGENTSAgents and subagents | Added between v2.1.266 and v2.1.269 Documented | — |
CLAUDE_CODE_WORKFLOW_PREFIX_STAGGER_MSAgents and subagents | Added in v2.1.229 Documented | — |
CLAUDE_CODE_WORKFLOW_PROMPT_PROVENANCEAgents and subagents | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_CODE_WORKFLOW_SIZE_WARNING_AGENTSAgents and subagents | Removed between v2.1.245 and v2.1.247 | — |
CLAUDE_CODE_WORKFLOW_SIZE_WARNING_TOKENSContext and compaction | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_CODE_WORKFLOW_SUBAGENT_MODELAgents and subagents | Added in v2.1.296 | Runs every workflow agent on the named model while other subagents keep their own. A value of inherit disables the override, and the existing… |
CLAUDE_CODE_WORKSPACE_HOST_PATHSOther | Added between v2.1.77 and v2.1.79 | Specifies host-side filesystem paths that should be mapped or accessible within a workspace context. This is relevant for containerized and remote development… |
CLAUDE_CODE_YOU_SHOULD_KNOW_DEBUGDebugging | Added in v2.1.286 Documented | — |
CLAUDE_CONFIG_DIROther | Present since v2.1.69 or earlier Documented | Custom config directory |
CLAUDE_CONTEXT_COLLAPSEContext and compaction | Removed between v2.1.269 and v2.1.283 | Collapses context on the fly, with a dedicated model to do it. A more aggressive context-management primitive than auto-compact, aimed at keeping long agentic… |
CLAUDE_CONTEXT_COLLAPSE_MODELContext and compaction | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_COWORK_MEMORY_EXTRA_GUIDELINESTerminal and UI | Added between v2.1.77 and v2.1.79 | Injects additional memory guidelines into cowork (teammate) sessions. In multi-agent "cowork" mode — where a leader spawns teammate Claude sessions in split… |
CLAUDE_COWORK_MEMORY_GUIDELINESTerminal and UI | Added between v2.1.118 and v2.1.123 | Policy document for the CoWork shared memory system — a new abstraction distinct from user memory (~/.claude/) and project memory (CLAUDE.md). Multiple agents… |
CLAUDE_COWORK_MEMORY_INDEX_CONTENTMemory and CLAUDE.md | Added between v2.1.118 and v2.1.123 | Content of the CoWork memory index. Where guidelines set policy, this carries structured summaries agents use to find relevant prior work without replaying… |
CLAUDE_COWORK_MEMORY_PATH_OVERRIDETerminal and UI | Present since v2.1.69 or earlier | — |
CLAUDE_DEBUGDebugging | Present since v2.1.69 or earlier | Enable debug logging |
CLAUDE_DISABLE_ADOPTFeature toggles | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_EFFORTModels and thinking | Added between v2.1.128 and v2.1.138 Documented | Set thinking effort level at spawn time without the interactive /effort picker. Scriptable effort control: run high effort on the architect agent, low effort… |
CLAUDE_ENABLE_BYTE_WATCHDOGNetwork and proxy | Added between v2.1.104 and v2.1.107 Documented | Activates a byte-level watchdog on API response streams. The v2.1.105 changelog describes a fix for stalled API streams: "streams now abort after 5 minutes of… |
CLAUDE_ENABLE_BYTE_WATCHDOG_BEDROCKCloud providers | Added between v2.1.138 and v2.1.143 Documented | Enable the byte watchdog on Bedrock connections. The watchdog fires when a connection opens but produces no bytes within a window — catching silent stalls that… |
CLAUDE_ENABLE_STREAM_WATCHDOGNetwork and proxy | Present since v2.1.69 or earlier Documented | Enable stream health monitoring |
CLAUDE_ENV_FILEOther | Present since v2.1.69 or earlier Documented | Path to environment file for session variables |
CLAUDE_FORCE_DISPLAY_SURVEYFeature toggles | Present since v2.1.69 or earlier | Force feedback survey display |
CLAUDE_GATEWAY_ALLOW_LOOPBACKOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_GATEWAY_DRAIN_TIMEOUT_MSNetwork and proxy | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_GATEWAY_LOG_LEVELDebugging | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_GATEWAY_PROXY_IS_EGRESS_BOUNDARYNetwork and proxy | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_IMPORT_CONVERSATIONSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_INTERNAL_ASSISTANT_TEAM_NAMEAgents and subagents | Added in v2.1.108 | Passes the current Agent Teams team name (prefixed assistant-) to a spawned child process. Agent Teams surfaces in the UI as "Agent Teams is not yet available… |
CLAUDE_INTERNAL_FC_OVERRIDESTerminal and UI | Added between v2.1.118 and v2.1.123 | Internal overrides for function-call (tool-use) behavior. Injects overrides that bypass normal routing — for testing new tool schemas or shadowing production… |
CLAUDE_IN_CHROME_DOMAIN_RULE_TOOLShell and tools | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_IN_CHROME_MANAGED_MCP_REFUSALMCP | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_IN_CHROME_MCP_SERVER_NAMEMCP | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_JOB_DIROther | Added between v2.1.118 and v2.1.123 Documented | Working directory for a background job, independent of the daemon's own cwd. Background jobs may target a different directory than the session that spawned… |
CLAUDE_LOCAL_OAUTH_API_BASEAuthentication | Added in v2.1.85 | Overrides the base URL for local OAuth API operations. This extends the auth customization story started by CLAUDE_AI_ORIGIN in v2.1.84, giving operators finer… |
CLAUDE_LOCAL_OAUTH_APPS_BASEAuthentication | Added in v2.1.85 | Overrides the base URL for the local OAuth applications registry. Together with CLAUDE_LOCAL_OAUTH_API_BASE, this completes a two-part override for the OAuth… |
CLAUDE_LOCAL_OAUTH_CONSOLE_BASEAuthentication | Added in v2.1.86 | Overrides the base URL for the OAuth console interface. This is the third piece of the local OAuth override triptych: CLAUDE_LOCAL_OAUTH_API_BASE handles token… |
CLAUDE_MEMORY_STORESMemory and CLAUDE.md | Added between v2.1.138 and v2.1.143 | Configure which memory backends are active. With the memory system now supporting typed files, project-scoped MEMORY.md indexes, and persistent cross-session… |
CLAUDE_MOCK_HEADERLESS_429Other | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_NAMESOther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_PIDOther | Added between v2.1.212 and v2.1.215 Documented | Holds the CLI's own process ID and powers a self-protection shim: the injected shell wrapper around pkill/pgrep refuses to signal any match equal to… |
CLAUDE_PLUGIN_DATAPlugins and skills | Added between v2.1.77 and v2.1.79 | Provides a filesystem path where plugins can store persistent state that survives plugin updates and reinstalls. Previously, plugin data lived alongside the… |
CLAUDE_PLUGIN_OPTION_Plugins and skills | — | A prefix-style variable (note the trailing underscore) for passing configuration options to installed plugins. This follows the pattern of… |
CLAUDE_PLUGIN_ROOTPlugins and skills | Present since v2.1.69 or earlier | Root directory for plugins |
CLAUDE_PREVIEW_CLASSIFIER_FLOOROther | Removed between v2.1.241 and v2.1.245 | — |
CLAUDE_PROJECT_DIROther | Present since v2.1.69 or earlier | Override project directory |
CLAUDE_PROJECT_UUIDOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_PTY_HEARTBEAT_MSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_PTY_HOST_EXECOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_PTY_HOST_NO_STABLE_PATHOther | Added in v2.1.295 | — |
CLAUDE_PTY_ORPHAN_CHECK_MSOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_PTY_RECORDOther | Added between v2.1.118 and v2.1.123 | Enables PTY session recording for a background agent — captures the raw terminal byte stream as a bit-for-bit replay artifact, not just a transcript. Likely… |
CLAUDE_RELAUNCH_SESSION_ADD_DIRSSessions | Removed in v2.1.310 | — |
CLAUDE_REMOTE_CONTROL_SESSION_NAME_PREFIXSessions | Added in v2.1.92 Documented | Sets a prefix for Remote Control session names. The changelog[1] mentions improved session naming for Remote Control — this variable lets teams enforce naming… |
CLAUDE_REMOTE_TOOLS_BRIDGE_URLNetwork and proxy | Added between v2.1.224 and v2.1.227 | — |
CLAUDE_REMOTE_WORKFLOW_ARGSAgents and subagents | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_REMOTE_WORKFLOW_SCRIPTAgents and subagents | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_REPL_MODEOther | Removed between v2.1.96 and v2.1.100 | Sets the operating mode for the REPL interface. This likely controls behavior such as output format (JSON vs plain text), verbosity level, or whether the REPL… |
CLAUDE_REPL_MODE0Other | — | Prototype naming for the REPL mode configuration. Replaced by the properly named CLAUDE_REPL_MODE in this release. |
CLAUDE_REPL_VARIANTOther | Removed between v2.1.269 and v2.1.283 | Selects which REPL implementation to load. Multiple variants coexist in the native binary; this key lets Anthropic A/B-test REPL behavior without separate… |
CLAUDE_REPL_VERBOSEOther | Removed between v2.1.269 and v2.1.283 | — |
CLAUDE_RUNNER_ACCOUNT_EMAILOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_ACCOUNT_IDOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_ACTIVITY_FDOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_RUNNER_ALIVE_EVERY_MSOther | Added between v2.1.307 and v2.1.309 | — |
CLAUDE_RUNNER_API_BASE_URLNetwork and proxy | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_ATTEMPTOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_CHECKOUT_PATHOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_CLAUDE_BINOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_CLIENT_PLATFORMOther | Added in v2.1.229 | — |
CLAUDE_RUNNER_CORRELATION_IDOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_DEBUG_LOG_PATHDebugging | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_DISABLE_AWAITING_ACTION_OVERRIDETerminal and UI | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_RUNNER_DISABLE_TURN_BEGAN_BEFORE_INITFeature toggles | Added between v2.1.307 and v2.1.309 | — |
CLAUDE_RUNNER_EXIT_REASONOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_FAIL_FAST_FETCHOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_FETCH_DEPTHOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_RUNNER_FETCH_SERVER_PROGRESS_CAP_MSOther | Added in v2.1.295 | On a self-hosted runner, caps how long a git fetch keeps waiting while the server is still reporting progress on a large repository. Takes milliseconds,… |
CLAUDE_RUNNER_GIT_MOUNT_URLNetwork and proxy | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_ORDER_IDOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_ORDER_SERVER_TIMEOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_POOL_IDOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_PRIMARY_REPO_REVISIONOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_PRIMARY_REPO_URLNetwork and proxy | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_REPO_REFOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_REPO_SOURCESOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_REPO_URLNetwork and proxy | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_SESSION_IDSessions | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_SESSION_UUIDSessions | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_SKIP_GIT_VERIFYFeature toggles | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_STALL_GIVEUPOther | Added between v2.1.241 and v2.1.245 | — |
CLAUDE_RUNNER_TRUST_CANONICAL_PREWARMOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_UPDATE_BINOther | Added in v2.1.307 | — |
CLAUDE_RUNNER_USE_GIT_PROXYNetwork and proxy | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_WORKSPACE_PATHSOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_RUNNER_WORK_ORDER_FILEOther | Added between v2.1.222 and v2.1.224 | — |
CLAUDE_SCRIPT_HOOK_ACKOther | Added between v2.1.252 and v2.1.266 | — |
CLAUDE_SDK_CAN_USE_TOOL_SHADOWEDShell and tools | Removed in v2.1.305 | — |
CLAUDE_SECURESTORAGE_CONFIG_DIROther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_SERVE_DRAIN_TIMEOUT_MSNetwork and proxy | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_SESSION_INGRESS_TOKEN_FILEAuthentication | Added between v2.1.79 and v2.1.83 | — |
CLAUDE_SLOW_FIRST_BYTE_MSOther | Added between v2.1.108 and v2.1.114 | Default 30,000ms. Logs a "Slow first byte: no stream chunk" observability event when the connection opens but produces no chunks within the window. Complements… |
CLAUDE_SNIPOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_SSH_DAEMON_CHILDOther | Added in v2.1.299 | — |
CLAUDE_SSH_LOCAL_BINARYOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_SSH_RUN_DIROther | Added in v2.1.299 | — |
CLAUDE_SSH_VERSIONOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_STAGE_FILE_ROOTOther | Added between v2.1.143 and v2.1.212 | — |
CLAUDE_STREAM_FIRST_BYTE_TIMEOUT_MSNetwork and proxy | Added between v2.1.241 and v2.1.245 Documented | — |
CLAUDE_STREAM_IDLE_TIMEOUT_MSNetwork and proxy | Added in v2.1.84 Documented | Configures the streaming idle watchdog threshold — the maximum time Claude Code waits for data on an open SSE connection before treating it as stalled. The… |
CLAUDE_SUBAGENT_BG_SHELL_MAX_MSAgents and subagents | Removed between v2.1.252 and v2.1.266 Documented | Time cap for shell commands run by background subagents. A background agent running a full test suite or a slow build command used to be bounded only by the… |
CLAUDE_TEST_ESSENTIAL_TRAFFICOther | Added in v2.1.310 | — |
CLAUDE_TEST_HEADEDOther | Added in v2.1.305 | — |
CLAUDE_TEST_NO_OPENOther | Added in v2.1.310 | — |
CLAUDE_TEST_PROJECT_DIROther | Added between v2.1.269 and v2.1.283 | — |
CLAUDE_TMPDIROther | Present since v2.1.69 or earlier | Alternative temp directory; fallback for CLAUDE_CODE_TMPDIR |
CLAUDE_TRUSTED_DEVICE_TOKENAuthentication | Added in v2.1.86 | Stores a token that marks the current device as trusted, likely enabling persistent authentication sessions without repeated re-authorization. |
CLAUDE_WORKFLOW_NAME_ONLYAgents and subagents | Added between v2.1.143 and v2.1.212 | Restricts a remote/headless run to a single named workflow. It appears immediately after CLAUDE_REMOTE_WORKFLOW_SCRIPT and CLAUDE_REMOTE_WORKFLOW_ARGS in the… |
CLAUDE_WORKSHOP_PROGRESSOther | Removed in v2.1.310 | — |
DATABASE_URLNetwork and proxy | — Documented | — |
DEBUGDebugging | — Documented | — |
DISABLE_AUTOUPDATERFeature toggles | — Documented | Automatic update checker |
DISABLE_AUTO_COMPACTContext and compaction | — Documented | Disable automatic compaction only (manual /compact still works) |
DISABLE_AUTO_MIGRATE_TO_NATIVEFeature toggles | — | Native installer migration |
DISABLE_BUG_COMMANDFeature toggles | — | /bug command |
DISABLE_CLAUDE_CODE_SM_COMPACTContext and compaction | — | Disable session memory compaction |
DISABLE_COMPACTContext and compaction | — Documented | Disable all compaction (manual + auto) |
DISABLE_COST_WARNINGSFeature toggles | — Documented | API cost warnings |
DISABLE_DOCTOR_COMMANDFeature toggles | — Documented | /doctor diagnostic command |
DISABLE_ERROR_REPORTINGFeature toggles | — Documented | Automatic error reporting |
DISABLE_EXTRA_USAGE_COMMANDFeature toggles | — Documented | Extra usage display |
DISABLE_FEEDBACK_COMMANDFeature toggles | — Documented | /feedback command |
DISABLE_GROWTHBOOKFeature toggles | — Documented | — |
DISABLE_INSTALLATION_CHECKSFeature toggles | — Documented | Installation verification |
DISABLE_INSTALL_GITHUB_APP_COMMANDFeature toggles | — Documented | GitHub app install command |
DISABLE_INTERLEAVED_THINKINGModels and thinking | — Documented | Interleaved thinking beta |
DISABLE_LOGIN_COMMANDDebugging | — Documented | /login command |
DISABLE_LOGOUT_COMMANDDebugging | — Documented | /logout command |
DISABLE_MICROCOMPACTContext and compaction | — | Micro-compaction (small context cleanups) |
DISABLE_PROMPT_CACHINGFeature toggles | — Documented | Prompt caching globally |
DISABLE_PROMPT_CACHING_FABLEModels and thinking | — Documented | — |
DISABLE_PROMPT_CACHING_HAIKUModels and thinking | — Documented | Prompt caching for Haiku |
DISABLE_PROMPT_CACHING_OPUSModels and thinking | — Documented | Prompt caching for Opus |
DISABLE_PROMPT_CACHING_SONNETModels and thinking | — Documented | Prompt caching for Sonnet |
DISABLE_TELEMETRYTelemetry | — Documented | All telemetry |
DISABLE_UPDATESFeature toggles | — Documented | Explicitly documented in the v2.1.118 changelog. Prevents Claude Code from auto-checking for or applying npm updates. Intended for environments where updates… |
DISABLE_UPGRADE_COMMANDFeature toggles | — Documented | /upgrade command |
DO_NOT_TRACKOther | — Documented | — |
ENABLE_BETA_TRACING_DETAILEDFeature toggles | — Documented | Enable detailed beta tracing |
ENABLE_BTWFeature toggles | — | Enable "by the way" suggestions |
ENABLE_CLAUDEAI_MCP_SERVERSMCP | — Documented | Enable Claude.ai-hosted MCP servers |
ENABLE_CLAUDE_CODE_SM_COMPACTContext and compaction | — | Force enable session memory compaction |
ENABLE_ENHANCED_TELEMETRY_BETATelemetry | — | Enable enhanced telemetry (beta) |
ENABLE_LSP_TOOLShell and tools | — | Enable Language Server Protocol tool |
ENABLE_MCP_LARGE_OUTPUT_FILESMCP | — | Enable large output files for MCP |
ENABLE_PROMPT_CACHING_1HFeature toggles | — Documented | — |
ENABLE_PROMPT_CACHING_1H_BEDROCKCloud providers | — Documented | Enable 1-hour prompt caching on Bedrock |
ENABLE_SESSION_BACKGROUNDINGSessions | — | Enable session backgrounding |
ENABLE_TOOL_SEARCHShell and tools | — Documented | Tool search/deferred loading: auto, true, false, or 0–100% |
FORCE_AUTOUPDATE_PLUGINSPlugins and skills | — Documented | Force auto-update plugins |
FORCE_HYPERLINKFeature toggles | — Documented | — |
FORCE_PROMPT_CACHING_5MFeature toggles | — Documented | — |
GITHUB_TOKENAuthentication | — Documented | — |
GIT_CONFIG_COUNTOther | — Documented | — |
HTTPS_PROXYNetwork and proxy | — Documented | HTTPS proxy server URL |
HTTP_PROXYNetwork and proxy | — Documented | HTTP proxy server URL |
IS_DEMOOther | — Documented | Indicates demo mode |
MAX_MCP_OUTPUT_TOKENSContext and compaction | — Documented | Max tokens for MCP tool output |
MAX_STRUCTURED_OUTPUT_RETRIESNetwork and proxy | — Documented | — |
MAX_THINKING_TOKENSModels and thinking | — Documented | Likely controlled via API settings now |
MCP_CLIENT_SECRETMCP | — Documented | Client secret for MCP OAuth |
MCP_CONNECTION_NONBLOCKINGNetwork and proxy | — Documented | Make MCP connections non-blocking |
MCP_CONNECT_TIMEOUT_MSNetwork and proxy | — Documented | — |
MCP_DISCOVERY_CACHEMCP | — Documented | — |
MCP_DISCOVERY_CACHE_MAX_STALE_SMCP | — Documented | — |
MCP_DISCOVERY_CACHE_STRIKESMCP | — Documented | — |
MCP_DISCOVERY_CACHE_TTL_SMCP | — Documented | — |
MCP_OAUTH_CALLBACK_PORTAuthentication | — Documented | OAuth callback server port |
MCP_PROTOCOL_NEGOTIATIONMCP | — Documented | — |
MCP_REMOTE_SERVER_CONNECTION_BATCH_SIZENetwork and proxy | — Documented | Remote MCP connection batch size |
MCP_SDK_GENERATIONMCP | — Documented | — |
MCP_SERVER_CONNECTION_BATCH_SIZENetwork and proxy | — Documented | Concurrent MCP server connections |
MCP_TIMEOUTNetwork and proxy | — Documented | MCP server connection timeout |
MCP_TOOL_TIMEOUTNetwork and proxy | — Documented | Individual MCP tool execution timeout |
NO_PROXYNetwork and proxy | — Documented | Domains to bypass proxy (comma-separated) |
NPM_TOKENAuthentication | — Documented | — |
OTEL_ATTRIBUTE_VALUE_LENGTH_LIMITTelemetry | — Documented | — |
OTEL_LOG_ASSISTANT_RESPONSESTelemetry | — Documented | — |
OTEL_LOG_MANAGED_SETTINGSTelemetry | — Documented | — |
OTEL_LOG_RAW_API_BODIESTelemetry | — Documented | — |
OTEL_LOG_TOOL_CONTENTTelemetry | — Documented | Include tool input/output in telemetry |
OTEL_LOG_TOOL_DETAILSTelemetry | — Documented | Include tool execution details |
OTEL_LOG_USER_PROMPTSTelemetry | — Documented | Include user prompts in telemetry |
OTEL_METRICS_INCLUDE_ACCOUNT_UUIDTelemetry | — Documented | — |
OTEL_METRICS_INCLUDE_ENTRYPOINTTelemetry | — Documented | — |
OTEL_METRICS_INCLUDE_REPOSITORYTelemetry | — Documented | — |
OTEL_METRICS_INCLUDE_RESOURCE_ATTRIBUTESTelemetry | — Documented | — |
OTEL_METRICS_INCLUDE_SESSION_IDTelemetry | — Documented | — |
OTEL_METRICS_INCLUDE_VERSIONTelemetry | — Documented | — |
PIP_INDEX_URLNetwork and proxy | — Documented | — |
SLASH_COMMAND_TOOL_CHAR_BUDGETShell and tools | — Documented | Character budget for slash command tool output |
TASK_MAX_OUTPUT_LENGTHOther | — Documented | Max output length for Task tool results |
USE_BUILTIN_RIPGREPOther | — Documented | Force use of built-in ripgrep |
VERTEX_REGION_CLAUDE_3_5_HAIKUCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_3_5_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_3_7_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_0_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_0_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_1_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_5_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_5_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_6_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_6_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_7_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_4_8_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_5_5_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_5_5_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_5_OPUSCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_5_SONNETCloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_FABLE_5Cloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_FABLE_5_1Cloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_HAIKU_4_5Cloud providers | — Documented | — |
VERTEX_REGION_CLAUDE_HAIKU_5_5Cloud providers | — Documented | — |