# Print mode

Run one prompt, write the answer to stdout, and exit. Print mode exits non-zero when the answer fails, which makes Eva safe inside a shell pipeline.

Print mode answers one prompt and exits. It is how Eva belongs in a script.

```bash
eva --print "summarise the last commit"
```

`-p` is the short form.

## It is safe in a pipeline

**Print mode exits non-zero when the answer fails.** A pipeline that checks
exit codes therefore stops on a failed run rather than carrying an empty
answer forward.

```bash
eva -p "list the risky changes in this diff" > review.txt || exit 1
```

| Code | When                                                               |
| ---- | ------------------------------------------------------------------ |
| 0    | the Run ended `done`                                               |
| 1    | a parse error, an unreadable config, or a Run that ended otherwise |
| 130  | the second <kbd>Ctrl</kbd>+<kbd>C</kbd>                            |

[Exit codes](/reference/exit-codes) has the full table, including the codes the
other commands return.

## The prompt is a flag, not a bare argument

`eva --print "…"` rather than `eva "…"`. The prompt stays behind the flag on
purpose: with a bare argument accepted, a misspelled verb becomes a valid
prompt. `eva trsut` would be sent to a model rather than corrected.

## Combine it with the global flags

Every global flag works in print mode.

```bash
eva -p "explain this error" --model anthropic/claude-sonnet-5
eva -p "review the diff" --config ./ci.eva.yaml
eva -p "what changed?" --without-plugin eva.themes
```

## A finding does not fail the run

An unread config key is a finding. Eva writes it to stderr and the run
continues, with the exit code unchanged. A finding is data about your setup,
not a failure of the work.


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