Environment variables (reference)

The environment variables murk reads, and the CLI flags they mirror where one exists. This is the terse reference; the narrative version with resolution order and interactions lives in the Environment variables concept page.

Identity and vault selection

Variable	Description
`MURK_KEY`	Your raw age private key (`AGE-SECRET-KEY-1…`), inline. Rejected for hardware-plugin identity strings (`AGE-PLUGIN-…`) — use `MURK_KEY_FILE` for those.
`MURK_KEY_FILE`	Path to a private-key file: a raw age key, an SSH PEM key, or an age plugin identity file. `murk init` writes this reference into `.env`.
`MURK_VAULT`	Vault filename, defaulting to `.murk`. Equivalent to passing `--vault` on every command (the one variable in the clap model).

Safety and agent context

Variable	Description
`MURK_STRICT`	Truthy fails closed rather than let a secret touch disk, and disables the automatic key lookup under `~/.config/murk/keys`.
`MURK_AGENT`	Marks the process as running for an AI agent. Forces strict mode unconditionally; `murk agent exec` sets it on its child.
`MURK_SELF_SCOPE`	Truthy holds your own key to the vault’s agent allow-tag policy, as if you were an agent. Implied inside an agent context.
`MURK_NO_SIGNER_PIN`	Opts out of signer-registry pinning (TOFU) on load — an escape hatch for a deliberate signer-key change, not for everyday use.

Also honored

Variable	Description
`CI`	Truthy prints a one-line nudge toward the scoped-agent path when a pipeline decrypts with a personal key. Advisory only.
`EDITOR, VISUAL`	Editor launched by `murk edit`, checking `EDITOR` then `VISUAL`, falling back to `vi`.
`XDG_RUNTIME_DIR`	Preferred (typically tmpfs) scratch location for `murk edit`’s temporary file, over `/tmp`.
`HOME (USERPROFILE on Windows)`	Base directory for murk state: `~/.config/murk/keys`, `agent-keys`, and `signer-pins`.