# Consult Codex

> Multi-turn consultation with Codex CLI for second opinions, brainstorming, or collaborative problem-solving. Use when the user asks to "consult codex", "ask codex", "get codex's opinion", "brainstorm with codex", "discuss with codex", or "chat with codex".

- Skill: `majiayu000/consult-codex-3` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds add majiayu000/consult-codex-3`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/consult-codex-3/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/consult-codex-3

---


# Consult Codex

Multi-turn consultation with Codex CLI. Maintains a conversation across multiple turns using session persistence, unlike single-shot `/codex-exec`.

## Step 1: Gather Context

Identify the 2-5 files most relevant to the problem. Formulate a clear, specific question. Include what has been tried and relevant constraints.

## Step 2: Start Session

Run `codex exec` with `-o` to capture the response cleanly. Default to `-s read-only` for safety. Use `-s workspace-write` when the consultation requires running code or reading files outside the workspace.

**All `codex` Bash calls require `dangerouslyDisableSandbox: true`** (network access to OpenAI API). Use `.turbo/` as the temp directory — it is in the working directory (sandbox-writable), gitignored, and avoids `$TMPDIR` path mismatches between sandbox and non-sandbox mode.

**Non-piped `codex exec` invocations require `< /dev/null`** to avoid hanging on stdin. Codex reads from stdin whenever stdin is non-TTY, and in subprocess contexts the harness leaves stdin connected to a pipe that never EOFs — codex blocks forever, printing only `Reading additional input from stdin...`. The piped form (`cat file | codex exec "..."`) is safe — `cat` closes the pipe after the file.

Generate a random session tag at the start to keep files unique for parallel use:

```bash
CODEX_TAG=$(head -c 4 /dev/urandom | xxd -p) && mkdir -p .turbo/codex
codex exec -s read-only -o ".turbo/codex/$CODEX_TAG.txt" "<question with full context>" < /dev/null
```

### Prompt Shaping

Structure the question using XML tags for clearer Codex responses:

- `<task>`: The concrete question and relevant context.
- `<compact_output_contract>`: Desired output shape and brevity requirements.
- `<structured_output_contract>`: Same purpose but for structured/schema responses.
- `<grounding_rules>`: When claims must be evidence-based (review, research, root-cause analysis).
- `<dig_deeper_nudge>`: Push past surface-level findings to check for second-order failures.
- `<verification_loop>`: When correctness matters — ask Codex to verify before finalizing.

Example prompt for a diagnosis question:

```
<task>Diagnose why the auth middleware rejects valid tokens after the session refactor.</task>
<compact_output_contract>Return: (1) most likely root cause, (2) evidence, (3) smallest safe next step.</compact_output_contract>
<grounding_rules>Ground every claim in the provided context or tool outputs. Label hypotheses explicitly.</grounding_rules>
```

For correctness-critical questions, add `<verification_loop>` asking Codex to verify its answer before finalizing.

Keep prompts compact, with tight output contracts. One clear task per Codex turn.

For long context that won't fit inline, write a context file and pipe it via stdin. The prompt stays as the argument, context pipes in as `<stdin>` automatically:

```bash
cat > ".turbo/codex/$CODEX_TAG-ctx.txt" << 'EOF'
<long context here>
EOF
cat ".turbo/codex/$CODEX_TAG-ctx.txt" | codex exec -s read-only -o ".turbo/codex/$CODEX_TAG.txt" "<question>"
```

Parse the `session id:` line from the CLI output. This UUID is needed for follow-up turns.

Use a generous timeout (30 minutes / 1800000ms per turn).

## Step 3: Read and Evaluate Response

The `-o` file contains only Codex's response (cleaner than stdout, which includes CLI chrome and tool-use logs). Read from `.turbo/codex/$CODEX_TAG.txt`. If the output is too large for the Read tool, read stdout from the Bash tool result instead.

Assess whether:
- The answer is sufficient and actionable
- Follow-up questions would improve the answer
- The response contradicts known project facts (verify before accepting)

If no follow-up is needed, skip to the Synthesize step.

## Step 4: Follow Up

Resume the session with the parsed session ID (not `--last`, which is unsafe for parallel use):

```bash
codex exec resume <session-id> -o ".turbo/codex/$CODEX_TAG.txt" "<follow-up question>" < /dev/null
```

The `-s` flag is not available for `resume`. It inherits sandbox settings from the original session.

Return to Step 3. Cap at 5 turns to prevent runaway conversations.

## Step 5: Synthesize

Summarize the key insights from the consultation. Cross-reference suggestions with project documentation and conventions before applying. Codex suggestions are starting points, not guaranteed solutions.