| name | promptgen |
| description | Turn rough instructions into stronger prompts using the source workflow at `claude/promptgen`. Use when the user wants a task prompt, system prompt, coding-agent prompt, tool description, eval grader, subagent briefing, or prompt-improvement pass rather than direct execution. |
| metadata | {"short-description":"Turn rough asks into prompts","version":"3.0.0"} |
Promptgen
Use this skill when the user wants a rough task description turned into a stronger prompt instead of asking Codex to perform the underlying task.
This is a thin Codex wrapper around claude/promptgen/skills/promptgen/SKILL.md. Reuse the source workflow, references, scripts, and eval material from the Claude skill directory instead of maintaining duplicated Codex copies.
Use This Skill
- The user wants a rough task description turned into a stronger prompt.
- Targets: task prompts, system prompts, coding-agent prompts, tool descriptions, eval graders, subagent briefings, three-agent harness instructions, prompt-improvement requests.
Do Not Use This Skill
- Do not use this skill when the user wants the underlying task completed directly.
Source Material
- Source skill:
claude/promptgen/skills/promptgen/SKILL.md
- Source directory:
claude/promptgen/skills/promptgen/
- Codex metadata:
agents/openai.yaml
Load only the source files needed for the current task. Do not recreate or copy the Claude-side bundled resources into this Codex skill.
Workflow
- Treat
claude/promptgen/skills/promptgen/SKILL.md as the source workflow and ignore Claude-only invocation wiring.
- Read the needed source references from
claude/promptgen/skills/promptgen/references/. The references cover prompt principles, mechanics, structure templates, security patterns, code-for-agents rules, and anti-patterns.
- Before generation, read
prompt-mechanics.md for the prompt brief and specificity dial; read prompt-structure.md to pick the target template (Claude / GPT / Codex / generic) and any prompt-type insert (subagent briefing, three-agent harness, eval grader).
- Use
prompt-principles.md for evidence-backed defaults, model-generation gotchas, and reasoning-effort / verbosity calibration.
- Use
security-patterns.md only when the prompt's target agent will face untrusted input, MCP tools, RAG, or the lethal trifecta. Apply Meta's Rule of Two when state-changing actions are in scope.
- Run the
anti-patterns.md self-check before returning the prompt; audit explicitly for contradictions.
- If current repo facts matter (file paths, naming conventions, build / test commands, framework versions), inspect the repo before finalizing the generated prompt.
Codex Notes
- Ignore Claude-only frontmatter and runtime wiring such as tool allowlists, invocation metadata, Claude argument variables, and Claude skill-directory environment variables.
- Infer inputs from the user request and local context before asking follow-up questions. Bias to action over clarification - persist end-to-end within a single turn whenever feasible.
- Apply scope discipline when generating Codex-targeted prompts: implement EXACTLY and ONLY what the user requests; do not invent extra features or UX embellishments.
- Prefer
--for codex mechanics when the target prompt is for Codex, repo edits, code review, CI repair, or long-running coding-agent work.
- For Codex-targeted prompts, allow short preambles every 1-3 logical steps; hard floor every 6 steps or 10 tool calls. Do not require routine progress preambles for non-interactive rollouts.
- Recommend
reasoning_effort (none | minimal | low | medium | high | xhigh) and verbosity tuning at the API level instead of writing prose that approximates them. Default none on GPT-5.2; calibrate up only for genuinely complex multi-step work.
- Prefer dedicated tools over shell. Always parallelize independent reads. Do not hard-code tool-call order unless the harness contract requires it.
- For long-running rollouts beyond a single context window, instruct the agent to write a structured progress file (JSON, less prone to model corruption than Markdown) at the end of each session and read it at the start of the next.
- For repo-wide durable norms, recommend documenting them in
AGENTS.md at the repo root (or nested per directory). Codex / Cursor / Copilot / Amp / Jules / Factory / Windsurf / Aider all read this file. Cap is 32 KiB (project_doc_max_bytes).
- Do not copy to clipboard unless the user explicitly asks for that side effect in the Codex session.
- If a source script or networked command fails because of sandbox restrictions, rerun it with escalation and a short justification.
- For destructive or irreversible actions, confirm intent unless the user was already explicit. Default Codex behavior: pause only for actions that risk data loss, security boundaries, or external impact.
- Promptgen itself runs in a single Codex agent loop. When the prompt you generate orchestrates Codex subagents (subagent briefing, three-agent harness), reflect Codex's real fan-out limits - default
agents.max_threads 6, close_agent to free completed slots (openai/codex#22779), and verify each subagent returned a payload (#16051) - instead of assuming Claude-style unlimited fan-out.
Verification
After any fix or state-changing action, rerun the narrowest relevant validator, script, listing command, or source check and compare the before / after result.
- Re-check the key output, diff, command result, or rendered text after you act.
- If the task changed files or external state, rerun the narrowest relevant validator, script, listing command, or source query.
- Report what was verified, what remains unverified, and any residual risk.
Examples
User: "Use Promptgen for this task."
Assistant: Opens `claude/promptgen/skills/promptgen/SKILL.md`, loads only the needed source references or scripts, adapts the workflow to Codex conventions, and completes the task.
User: "Apply the Promptgen workflow here."
Assistant: Reuses the source material from `claude/promptgen/skills/promptgen/` instead of relying on duplicated Codex-side resources.
User: "Turn this into a Codex coding-agent prompt: 'fix the flaky checkout tests and verify the failure mode'."
Assistant: Builds a Codex variant from `prompt-structure.md` with explicit outcome contract, done-when criteria, narrow verification command, scope discipline, and a single-turn persistence rule. Skips routine final reminders.