Reference · Exit codes

Exit codes

The CLI uses two exit code spaces: clap's defaults for argument parsing, and one NCI-specific code for “the symbol id you asked about does not exist”. Anything else surfaces as a generic failure.

Codes

Code	When it fires
`0`	Command succeeded.
`2`	Two unrelated cases share this code: Argument / usage error from clap — e.g. an unknown flag. NCI’s `EXIT_QUERY_NOT_FOUND`: `nci query show`, `snippet`, or `overloads` received a stable id that does not match any indexed row. Stderr carries the “recover the right id with `query find` / `query symbol`” hint.
`3`	`nci upgrade --check` found a newer release.
`1`	Generic runtime failure — anything not covered above. The error message lives on stderr; on JSON-format commands it is also echoed inside the `{"ok":false,"error":…}` envelope.
`130`	SIGINT (Ctrl-C). Platform default — NCI does not set it explicitly.

Reading the JSON envelope

For commands that support --format json, failures print { "ok": false, "error": "<string>" } to stdout — error is a single human-readable string, not an object (see json_err in packages/nci-engine/src/cli.rs). There is no separate kind / message split in the binary today.

For the success envelopes and data shapes used by nci query, see JSON output schemas.