Environment Variables

OMK uses environment variables in three ways:

• Variables such as OMK_OFFLINE configure the OMK process.
• OMK sets OMK_CODING_AGENT so child processes can detect that they run inside OMK.
• Commands run by the LLM-callable bash tool receive PI_* variables describing the current session.

Provider API-key variables are documented separately in Providers.

Process Marker

The CLI and RPC entry points set OMK_CODING_AGENT=true. Child processes inherit it and can use it to detect that they run inside OMK. It is not session-specific and is not set automatically when OMK is embedded through the SDK.

Bash Tool Session Environment

Commands run by the bash tool receive the current session state (the PI_* names are kept for upstream Pi compatibility):

Variable	Description
PI_SESSION_ID	Current session ID
PI_SESSION_FILE	Absolute path to the current session JSONL file; unset for ephemeral sessions
PI_PROVIDER	Currently selected model provider
PI_MODEL	Currently selected model ID
PI_REASONING_LEVEL	Current effective reasoning level: off, minimal, low, medium, high, xhigh, or max

The values are resolved when each command starts. Switching models or changing the reasoning level therefore affects the next bash command without restarting OMK. PI_PROVIDER and PI_MODEL identify the selected OMK model, not a different upstream model that a router may choose internally.

Inherited parent-process values for these variables are always stripped first, so a nested OMK session never exposes stale parent-session metadata.

When asked which model or provider is running, inspect these variables instead of inferring the answer from the system prompt:

printf '%s/%s\n' "$PI_PROVIDER" "$PI_MODEL"
printf 'reasoning=%s session=%s\n' "$PI_REASONING_LEVEL" "$PI_SESSION_ID"

The session file can be inspected directly when the session is persistent:

if [ -n "$PI_SESSION_FILE" ]; then
  tail -n 1 "$PI_SESSION_FILE"
fi

These variables are injected into the LLM-callable bash tool. They are not injected into user-entered ! or !! commands.

Custom Bash Tools

Bash tools created with createBashTool() expose the session environment by default. Injection happens before spawnHook, so a hook receives the variables in ctx.env:

const bashTool = createBashTool(cwd, {
  spawnHook: (ctx) => ({
    ...ctx,
    env: { ...ctx.env, CI: "1" },
  }),
});

Disable session metadata independently of the spawn hook:

const bashTool = createBashTool(cwd, {
  exposeSessionEnvironment: false,
  spawnHook: (ctx) => ctx,
});

When disabled, OMK removes inherited values for these variables so nested OMK processes do not expose stale parent-session metadata.

OMK Process Configuration

These variables are read by OMK itself:

Variable	Description
OMK_CODING_AGENT_DIR	Override the config directory; default is ~/.omk/agent
OMK_CODING_AGENT_SESSION_DIR	Override session storage; overridden by --session-dir
OMK_PACKAGE_DIR	Override the package directory, useful for Nix/Guix store paths
OMK_OFFLINE	Disable startup network operations, including update checks and install/update telemetry
OMK_SKIP_VERSION_CHECK	Disable the latest-version request
OMK_TELEMETRY	Override install/update telemetry and provider attribution headers: 1/true/yes or 0/false/no
OMK_SHARE_VIEWER_URL	Override the base URL used by /share
OMK_HARDWARE_CURSOR	Set to 1 to show the hardware cursor; see Terminal setup
OMK_CONTEXT_GOVERNOR	Configure the context-budget governor; see context-budget-* sources
OMK_VERIFIED_BASH	Default-on verified bash adapter for AgentSession/CLI bash. Set to 0 to opt out and use the legacy unverified path (see SDK — Evidence and Verification)
OMK_BASH_SANDBOX	Session bash sandbox mode: enforce by default (macOS sandbox-exec / Linux bwrap, workspace/temp writes only, network disabled, fail closed without a backend); explicit audit keeps an unwrapped ledger-only compatibility path; 0/off disables the preflight. Unknown values resolve to enforce
LIVE_E2E	Test-only: keep provider credentials so live-API e2e suites run on purpose (default scrubbed for hermetic tests)
OMK_OMP_SEAMS	Default-on OMP pure seams for read/grep. Set to 0 to opt out
VISUAL, EDITOR	External editor fallback when externalEditor is unset
HTTP_PROXY, HTTPS_PROXY	Proxy outbound HTTP requests

Provider credentials such as ANTHROPIC_API_KEY, OPENAI_API_KEY, and cloud-provider configuration are listed in Providers.