165 Environment Variables in Claude Code 2.1.69 — What Changed in 50 Versions#

Published on March 5, 2026

Part of the Claude Code Version Tracker series. | Official Env Vars

Back in January 2025, I extracted 83 undocumented environment variables from Claude Code v2.1.19's binary. Fifty versions later, I reran the same extraction on v2.1.69 and the count nearly doubled: 165 env vars, 16 model IDs, and 41 Statsig feature gates.

Here is what is new, what got removed, and why it matters.

The Numbers#

v2.1.19 (Jan 2025)v2.1.69 (Mar 2026)
Environment variables83165
Model IDs in binary16
Statsig feature gates~16 known41
Dynamic configs~9 known30+

Biggest New Additions#

Plugin Ecosystem (6 new vars)#

Claude Code now has a full plugin system. Six new env vars control it:

VariablePurpose
CLAUDE_CODE_PLUGIN_CACHE_DIRLocal cache directory for downloaded plugins
CLAUDE_CODE_PLUGIN_GIT_TIMEOUT_MSGit clone timeout for plugin installation
CLAUDE_CODE_PLUGIN_SEED_DIRSeed directory for pre-installed plugins
CLAUDE_CODE_PLUGIN_USE_ZIP_CACHEUse zip-based caching instead of git
CLAUDE_CODE_SYNC_PLUGIN_INSTALLInstall plugins synchronously (block until done)
CLAUDE_CODE_SYNC_PLUGIN_INSTALL_TIMEOUT_MSTimeout for synchronous plugin install

This aligns with the enabledPlugins setting in settings.json where you can toggle community and official plugins.

mTLS / Enterprise Proxy Support (3 new vars)#

Mutual TLS support for enterprise environments:

VariablePurpose
CLAUDE_CODE_CLIENT_CERTPath to client certificate for mTLS
CLAUDE_CODE_CLIENT_KEYPath to client private key
CLAUDE_CODE_CLIENT_KEY_PASSPHRASEPassphrase for encrypted client key

If your org uses a corporate proxy with mutual TLS, these are the vars you need.

Background Tasks and Cowork (5 new vars)#

VariablePurpose
CLAUDE_AUTO_BACKGROUND_TASKSEnable automatic background task execution
CLAUDE_CODE_DISABLE_BACKGROUND_TASKSDisable background tasks entirely
CLAUDE_CODE_ENABLE_TASKSEnable the task system
CLAUDE_CODE_IS_COWORKIndicates running in cowork (multi-agent) mode
CLAUDE_CODE_USE_CCR_V2Use Claude Code Router v2 for cowork sessions

Context Window Controls (5 new vars)#

Fine-grained control over auto-compaction — the system that compresses your conversation when hitting token limits:

VariablePurpose
CLAUDE_AFTER_LAST_COMPACTInternal marker: post-compaction state
CLAUDE_AUTOCOMPACT_PCT_OVERRIDEOverride the auto-compaction trigger percentage
CLAUDE_CODE_DISABLE_PRECOMPACT_SKIPDisable skipping pre-compaction checks
CLAUDE_CODE_DISABLE_1M_CONTEXTDisable the extended 1M token context window
CLAUDE_CODE_FILE_READ_MAX_OUTPUT_TOKENSMax tokens for file read output

If you read my context window management guide, CLAUDE_AUTOCOMPACT_PCT_OVERRIDE is particularly interesting — it lets you control exactly when compaction triggers. See the dedicated CLAUDE_AUTOCOMPACT_PCT_OVERRIDE guide for recommended values, the 83% cap quirk, and use-case-specific settings.

Multi-Provider Auth (7 new vars)#

Claude Code now has explicit env vars for each cloud provider:

VariablePurpose
CLAUDE_CODE_USE_BEDROCKUse Amazon Bedrock as backend
CLAUDE_CODE_USE_VERTEXUse Google Vertex AI as backend
CLAUDE_CODE_USE_FOUNDRYUse Anthropic Foundry as backend
CLAUDE_CODE_SKIP_BEDROCK_AUTHSkip Bedrock authentication
CLAUDE_CODE_SKIP_VERTEX_AUTHSkip Vertex AI authentication
CLAUDE_CODE_SKIP_FOUNDRY_AUTHSkip Foundry authentication
CLAUDE_CODE_CUSTOM_OAUTH_URLCustom OAuth endpoint URL

Fast Mode and UI Controls#

VariablePurpose
CLAUDE_CODE_DISABLE_FAST_MODEDisable the /fast toggle that uses the same model with faster output
CLAUDE_CODE_DISABLE_TERMINAL_TITLEStop Claude Code from setting the terminal title
CLAUDE_CODE_STREAMING_TEXTControl streaming text display
CLAUDE_CODE_QUESTION_PREVIEW_FORMATFormat for permission question previews
CLAUDE_CODE_SEARCH_HINTS_IN_LISTShow search hints in tool list

Remote and Server Mode (4 new vars)#

VariablePurpose
CLAUDE_CODE_REMOTE_MEMORY_DIRMemory directory for remote sessions
CLAUDE_CODE_REMOTE_SEND_KEEPALIVESSend keepalive pings in remote mode
CLAUDE_CODE_SPAWNED_BY_SERVERIndicates process was spawned by a server
CLAUDE_CODE_RESUME_INTERRUPTED_TURNResume an interrupted agent turn

What Got Removed (6 vars)#

Removed VariableReplacement / Notes
CLAUDE_BASH_NO_LOGINReplaced by CLAUDE_CODE_SHELL_PREFIX
CLAUDE_CODE_AGENT_SWARMSReplaced by CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS
CLAUDE_CODE_SIMPLETONRenamed to CLAUDE_CODE_SIMPLE
CLAUDE_CODE_SESSION_IDLikely internalized / no longer exposed
CLAUDE_CODE_PROFILE_QUERYLikely merged into general profiling
MAX_THINKING_TOKENSLikely controlled via API settings now

Model IDs in the Binary#

The v2.1.69 binary contains references to these model IDs:

claude-3-haiku-20240307
claude-3-opus-20240229
claude-3-sonnet-20240229
claude-3-5-haiku-20241022
claude-3-5-sonnet-20240620
claude-3-5-sonnet-20241022
claude-3-7-sonnet-20250219
claude-4-opus-20250514
claude-code-20250219
claude-haiku-4-5-20251001
claude-opus-4-20250514
claude-opus-4-1-20250805
claude-opus-4-5-20251101
claude-sonnet-4-20250514
claude-sonnet-4-5-20250514
claude-sonnet-4-5-20250929

The full Claude 4.x model family is visible — from Sonnet 4 through Opus 4.5.

New Dynamic Configs#

Several new Statsig dynamic configs appeared, revealing internal feature toggles:

Config IDValueLikely Purpose
522643335variant: "interactive_menu"Interactive menu UI mode selector
4008157471variant: "user_intent"User intent classification system
3148619311fromMarketplace: truePlugin marketplace integration
2719998910fallback_available_warning_threshold: 0.5Model fallback warning threshold
3855860696scheduledDelayMillis: 5000, maxExportBatchSize: 200Telemetry export batching config
4189951994tokenThreshold: 0.92Auto-compaction triggers at 92% of context window

The tokenThreshold: 0.92 in config 4189951994 is worth noting — it confirms that auto-compaction triggers at 92% capacity, earlier than the ~95% many assumed.

What This Tells Us About Claude Code's Direction#

Fifty versions of env var growth paint a clear picture:

  1. Plugin ecosystem is real — Six new vars for plugin management means Anthropic is building an extensible platform, not just a CLI tool.
  2. Enterprise is a priority — mTLS, multi-provider auth (Bedrock/Vertex/Foundry), and org-level UUIDs show serious enterprise investment.
  3. Multi-agent is maturing — Swarms became Agent Teams, cowork got a v2 router, and background tasks enable truly autonomous agent workflows.
  4. Context management is getting smarter — Five new compaction-related vars suggest ongoing work on the 1M context window and how to manage it efficiently.

I plan to rerun this analysis periodically.

This analysis is conducted for independent security research and interoperability purposes under fair use principles. All trademarks belong to their respective owners. The information presented here documents publicly observable behavior of installed software and is not intended to circumvent any technological protection measures, infringe on intellectual property rights, or encourage unauthorized use. Use these findings at your own discretion.


Latest: Claude Code v2.1.72 — 6 New Environment Variables

Next: Claude Code v2.1.70 — 3 New Environment Variables

Previously: 83 Undocumented Claude Code Environment Variables (v2.1.19)

Related: Context Window Management Guide | CLAUDE_AUTOCOMPACT_PCT_OVERRIDE Guide | Claude Code Productivity Tips