| name | codex-planner |
| description | Delegate planning to Codex/GPT. Returns dense, AI-optimized plan (not prose). Caller specifies reasoning effort (high/xhigh) based on complexity. |
| context | fork |
| model | haiku |
| allowed-tools | ["Bash","Read","Glob","Grep"] |
Codex Planning Delegation
Delegate architecture and design work to Codex/GPT-5. Return response verbatim.
Input from Caller
The caller (main agent) should specify:
- Task description: What to plan
- Reasoning effort:
high or xhigh based on complexity
high: Most planning tasks
xhigh: Complex architecture, critical systems, novel problems
Process
- Gather: working directory, user request, relevant file paths
- Determine reasoning effort from caller's request (default:
high)
- Build 7-section prompt (template below)
- Execute:
codex exec -m gpt-5.2-codex -c model_reasoning_effort="[high|xhigh]" --sandbox read-only -C "[PROJECT_DIR]" "[PROMPT]"
- Return FULL output verbatim - do not summarize
7-Section Prompt Template
1. TASK: Design/plan [feature/system] for [goal].
2. EXPECTED OUTCOME: Implementation-ready plan in dense, AI-agent format.
3. CONTEXT:
- Architecture: [description or "explore codebase"]
- Relevant: [file paths/patterns]
- Goal: [what to build]
4. CONSTRAINTS:
- Must work with: [existing systems]
- Cannot change: [protected components]
- Patterns: [conventions to follow]
5. MUST DO:
- Explore codebase for existing patterns
- Ask clarifying questions if ambiguous
- Provide architecture decisions with rationale
- Break into actionable steps
- Identify edge cases
- Estimate effort (Quick/Short/Medium/Large)
6. MUST NOT DO:
- Write or edit files
- Over-engineer
- Assume unclear requirements
7. OUTPUT FORMAT:
Dense, AI-agent-optimized format. No prose paragraphs.
ARCHITECTURE:
- [bullet points, not sentences]
FILES:
- path/to/file.ts: [purpose, 5 words max]
STEPS:
1. [imperative, minimal]
2. [imperative, minimal]
EDGE CASES:
- [case]: [handling]
EFFORT: [Quick|Short|Medium|Large]
QUESTIONS: [if any, else omit section]
Output
Return Codex response verbatim. Format is intentionally terse for token efficiency.