Copilot CLI environment variables

Allow all permissions automatically (equivalent to --allow-all). Exactly true also trusts the working directory, loading its skills, plugins, MCP servers, and hooks.

On: true, 1, yes, on, y; off: false, 0, no, off, n, empty (case-insensitive)

Set to false to disable automatic updates of the CLI and first-party plugins.

false

Override the cache directory used for marketplace caches, auto-update packages, and other ephemeral data.

Defaults: ~/Library/Caches/copilot (macOS), $XDG_CACHE_HOME/copilot or ~/.cache/copilot (Linux), %LOCALAPPDATA%/copilot (Windows)

Linux only. Overrides the oom_score_adj bias on shell command process trees so the OOM killer reclaims a runaway child before the CLI.

Default 300; range -1000 to 1000; off disables

Comma-separated list of additional directories for custom instructions.

Editor command for interactive editing, checked after $VISUAL and $EDITOR.

Defaults to vi if none are set

Opt into HTTP/2 transport; HTTP/1.1 is the default.

1 or true

Enable restoring a session that was still open when the CLI process went away (temporarily opt-in).

1

GitHub hostname for Copilot CLI only, overriding GH_HOST.

Authentication token; takes precedence over GH_TOKEN and GITHUB_TOKEN. Fine-grained PATs with Copilot Requests permission and Copilot CLI or gh OAuth tokens are supported; classic ghp_ PATs are not.

Override the configuration and state directory; replaces the entire ~/.copilot path.

Default: $HOME/.copilot

Maximum UTF-8 byte size for tool output returned directly to the model.

Default 20480 (20 KiB)

Set to false to disable loading and persisting local MCP server tool snapshots for the entire process.

false

Set the AI model; ranks below --model and above the model settings key in precedence. Required when using a BYOK provider.

Request plan-then-autopilot (equivalent to --plan --mode autopilot); ignored with a warning when --mode, --autopilot, or --plan is passed.

1, true, yes, on

Enable (1) or disable (0) the decorative frame around the input prompt, overriding the PROMPT_FRAME experimental flag.

1, 0

Shell command that prints a fresh BYOK API key before each provider request; takes precedence over COPILOT_PROVIDER_API_KEY.

Path to a JSON file defining a BYOK provider and model registry (providers and models keys); takes precedence over legacy COPILOT_PROVIDER_* variables when it declares anything.

Default: <COPILOT_HOME>/providers.json

Comma-separated list of additional directories for skills.

Set to false to disable the plugins dashboard opened by bare /plugin, /mcp, and /skills, and the non-interactive copilot plugin commands.

false

Set to 0 or false to keep BYOK reasoning tokens across a session resume instead of stripping them (the default).

0, false

Maximum concurrent subagents per session.

Default 32; range 1 to 256

Maximum subagent nesting depth.

Default 4; range 1 to 128

Maximum seconds -p (and -p --autopilot) waits for pending background agents or shell commands before exiting.

Default 600; 0 exits immediately

GitHub hostname for both GitHub CLI and Copilot CLI; override with COPILOT_GH_HOST for Copilot CLI only.

Default: github.com

Authentication token; takes precedence over GITHUB_TOKEN (second precedence overall).

Authentication token (third precedence). Its value is redacted from output by default.

Set to true to load project extensions and allow extension management tools in prompt mode (-p) or direct workflow runs. Does not grant tool permissions.

true

Set to true to load repository hooks in prompt mode (-p).

true

Set to true to load workspace MCP sources in prompt mode (-p).

true

Set to true to disable rich diff rendering.

true

Set to false to use the system ripgrep instead of the bundled version.

false

true always uses tgrep (trigram-indexed search), bypassing the file-count threshold; false always uses ripgrep. When unset, tgrep is used automatically only in large Git repositories on non-virtualized filesystems.

true, false

Minimum file count for automatic tgrep indexed search; 0 removes only the file-count requirement.

Non-negative integer; default 10000 on Windows, 50000 elsewhere

Allow the web_fetch tool to reach localhost during development, bypassing its loopback block.

1

When set to 1, HTTP hooks may use non-TLS http://localhost, http://127.*, and http://[::1] URLs.

1

BYOK: the base URL of your model provider's API endpoint (required).

BYOK: the provider type. openai works with any OpenAI-compatible endpoint.

openai (default), azure, anthropic

BYOK: your API key for the provider; not required for providers without authentication such as a local Ollama instance.

BYOK: bearer token used for provider authentication when API-key authentication is not used.

BYOK: specifies the API protocol used when communicating with the provider.

BYOK (Azure only): the Azure OpenAI API version used for requests.

BYOK: the well-known model name used to identify model capabilities and token limits.

BYOK: the model name sent to the provider API; for Azure OpenAI, the deployment name.

BYOK: maximum number of prompt tokens allowed in a request.

BYOK: maximum number of tokens generated in a response.

The hostname of your GitHub Enterprise Server instance (required for the GHES provider).

A personal access token for the GitHub Enterprise Server instance; always required for GHES inference.

For GHES automation, set to the personal access token (or use GITHUB_ENTERPRISE_TOKEN) together with GH_HOST; takes precedence over gh auth login credentials for the same host.

Install script: custom install directory.

Default /usr/local as root, $HOME/.local otherwise

Install script: install a specific version.

Default: latest version

When an MCP server sets oidc: true, the CLI injects OIDC tokens into this variable (or suffixed GITHUB_COPILOT_OIDC_MCP_TOKEN_<SUFFIX> variants) referenced in a local server's env block.

Points to a persistent, writable directory for an installed plugin; expandable as ${PLUGIN_DATA} (aliases CLAUDE_PLUGIN_DATA, COPILOT_PLUGIN_DATA) in stdio server args, env, and cwd.

Set to true in the runtime environment to suppress automatic plugin discovery so only --plugin-dir directories load.

true

Explicitly enable OpenTelemetry export; not required if OTEL_EXPORTER_OTLP_ENDPOINT is set.

Default false

OTLP endpoint URL; setting it automatically enables OTel.

OTel exporter type; auto-selects file when COPILOT_OTEL_FILE_EXPORTER_PATH is set.

otlp-http (default), file

OTLP HTTP wire protocol for the otlp-http exporter.

http/json (default), http/protobuf

Override OTEL_EXPORTER_OTLP_PROTOCOL for traces only.

Override OTEL_EXPORTER_OTLP_PROTOCOL for metrics only.

Service name in resource attributes.

Default github-copilot

Extra resource attributes as comma-separated key=value pairs, percent-encoding special characters.

Capture full prompt, response, and tool argument content in OTel signals; may include sensitive data.

Default false

OTel diagnostic log level.

NONE, ERROR, WARN, INFO, DEBUG, VERBOSE, ALL

Write all OTel signals to this file as JSON-lines; setting it automatically enables OTel.

Instrumentation scope name for tracer and meter.

Default github.copilot

Auth headers for the OTLP exporter (for example, Authorization=Bearer token).