Instrument 14 / Codex automation

Build a `codex exec --json` command with an explicit Git check.

Generate one inspectable command for JSONL automation, ephemeral runs, constrained sandboxes, structured output, and the trusted-directory check.

Compose a bounded run

Make the target and output explicit.

The safe default keeps the Git repository check, uses a read-only sandbox, streams JSONL events, and avoids persisting session files.

PromptShell-safe quoting is applied automatically. Sandbox modeRead-only is the default for inspection and CI review.

Execution controls

Select only the flags the consumer of this run needs.

JSONL eventsAdd --json for automation. EphemeralDo not persist session files. Outside GitAdd --skip-git-repo-check. Ignore user configDo not load $CODEX_HOME/config.toml.

Output schema fileOptional JSON Schema for the final response. Final message fileOptional path for --output-last-message.

Generated commandBOUNDED

Copy into the intended repository

codex exec --json --ephemeral --color never --sandbox read-only 'Review this repository and return the highest-risk issue.'

Output streamJSONL

Git guardRequired

Session filesNot saved

Sandboxread-only

Run this from the repository you intend Codex to inspect.

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Three separate boundaries

Git check.
Confirms the command targets a repository unless deliberately skipped.

Sandbox.
Controls filesystem and command authority; it is independent of the Git check.

Output contract.
JSONL events, a final-message file, and a response schema solve different automation needs.

Current CLI contract

What each generated flag changes.

--json prints execution events as newline-delimited JSON. Parse one object per line instead of expecting a single JSON document.

--ephemeral runs without persisting session files. It does not change model or sandbox behavior.

--skip-git-repo-check allows execution outside a Git repository. Use it only when the working directory is already explicit and controlled.

--output-schema points to a JSON Schema for the final response. --output-last-message writes the last agent message to a file.

Codex exec guide

Fix the trusted-directory error without hiding the target.

The best fix is usually to run inside the intended repository. The skip flag is for deliberate non-Git automation, not a blanket trust setting.

Inspect the current OpenAI Codex exec source → Need project-doc settings? Build config.toml → Read the full Codex CLI technical guide →

What does codex exec --json output?

It streams Codex execution events to standard output as JSONL: one JSON object per line. This is useful for CI, logging, and event-driven automation.

How do I fix Not inside a trusted directory in Codex CLI?

Run Codex from the intended Git repository whenever possible. For a deliberate workflow outside Git, add --skip-git-repo-check and make the target directory unambiguous.

Does --skip-git-repo-check disable the Codex sandbox?

No. The flag only bypasses the Git-repository requirement. The sandbox and approval controls remain separate.

How do Codex output schema and last-message files differ?

--output-schema constrains the final response shape. --output-last-message saves the final agent message. --json separately streams the full event sequence.