tobihagemann/consult-codex

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:

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:

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):

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.