Delegate codebase exploration or scripted actions to a non-interactive Codex exec run (codex exec / codex e). Use when you want a subagent to read lots of code or take actions without human interaction, and you can accept CLI output and optional file changes as the result.
Installation
Details
Usage
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skills listSkill Instructions
name: subagent description: Delegate codebase exploration or scripted actions to a non-interactive Codex exec run (codex exec / codex e). Use when you want a subagent to read lots of code or take actions without human interaction, and you can accept CLI output and optional file changes as the result.
Subagent
When to use
- Delegate large codebase reading, searching, or multi-step actions to a non-interactive exec run.
- Offload scripted or CI-style tasks that should finish without questions.
Inputs / outputs
- Inputs: a prompt string; optional flags such as
--cd,--model,--json, or--full-auto. - Outputs: CLI output from the exec run; possible file edits in the target repo.
Prompt template
Use a structured prompt to keep exec runs focused:
Goal:
Scope/paths:
Constraints:
Deliverables:
Context:
Steps
- Decide the task and repo root; include constraints and expected deliverables in the prompt.
- Choose a model using
resources/references/codex-exec.mdheuristics. - Prefer resuming when the follow-up builds on the same context (e.g., providers after a repo overview, reviewing verbose test output, or continuing a multi-step investigation). Use
codex exec resume <SESSION_ID> "<prompt>". - Start a new run when the task changes repos, needs a clean context, or should branch into a separate thread (e.g., exploring three unrelated areas in parallel).
- Run
codex execdirectly with flags; attach images with-i/--imagewhen needed. Use--skip-git-repo-checkwhen running outside a Git repo. - Wait for completion; review output and any file changes.
- If the task references a plan directory, update
learnings.mdin that plan directory with key findings and decisions.
Result checklist
- Did it identify the right files and entry points?
- Are key decisions and rationale explicit?
- Are edits (if any) listed clearly?
- Are tests or verification steps noted?
Session tracking
- Always copy the exec
session idinto the main thread for resuming.
Safety
- Avoid
--yolounless inside an isolated runner. - Prefer
--full-autoor explicit sandbox settings when you need workspace changes. - Keep prompts specific about allowed paths and operations.
Resources
resources/references/codex-exec.mdincludes flags, model selection, and code-reading guidance.
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