Environment variables¶

This page lists environment variables that affect carrier.

User-facing variables¶

Variable	Used by	Meaning
`CARRIER_COLOR`	all human-readable output	Set `always`, `1`, or `true` to force colors; `never`, `0`, or `false` to disable.
`NO_COLOR`	all human-readable output	Any non-empty value disables colors.
`TERM`	all human-readable output	`TERM=dumb` disables colors.
`XDG_CONFIG_HOME`	config loading	Changes config path to `$XDG_CONFIG_HOME/carrier/config.toml`.
`HOME`	config and default paths	Used for `~` expansion and default XDG-style locations.
`SHELL`	`run`, `rerun`, `shell`	Used for metadata, shell fallback, and default shell mode program.
`EDITOR`	`rerun --edit`	Editor used to modify argv JSON before rerun.
`VISUAL`	`rerun --edit`	Fallback editor if `EDITOR` is not set.

These variables override the persistent [ui] color config setting for a single invocation. Precedence, highest first: NO_COLOR / TERM=dumb (always disable) → CARRIER_COLOR → [ui] color config → automatic TTY detection.

Color examples

Disable colors

NO_COLOR=1 carrier history

Force colors through a pipe

CARRIER_COLOR=always carrier failed | less -R

Disable colors permanently

[ui]
color = "never"

Captured command environment¶

By default, carrier run stores the command environment as JSON metadata:

Config

[storage]
capture_env = true

Inspect captured environment:

Show environment

carrier show 42 --env
carrier show 42 --json | jq '.env'

Values are redacted when displayed unless you pass --no-redact.

Warning

Environment variables often contain credentials. Keep redaction enabled when environment capture is enabled.

Disable capture:

Disable environment capture

[storage]
capture_env = false

Shell-mode variables¶

carrier shell and carrier attach set these variables in the child shell environment:

Variable	Purpose
`CARRIER_SESSION_ID`	Integer ID of the current shell session. Used by `carrier session label` to identify the current session.
`CARRIER_SHELL_STATE`	Path to temporary shell state JSON.
`CARRIER_NOTIFY`	Passes notification request into shell hook runs.
`CARRIER_NOTIFY_ALWAYS`	Passes always-notify request into shell hook runs.
`CARRIER_NO_REDACT`	Passes redaction override into shell hook runs.

CARRIER_SESSION_ID is the only variable intended for direct use. When running inside a tracked shell, omit the session ID argument to carrier session label and it will read from this variable:

Label current session from inside the shell

carrier session label backend-debug

The remaining variables are implementation details. Do not set them manually unless you are debugging shell mode internals.