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Run npx skillmds@latest add richfrem/codex-cli-agent in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

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Is Codex CLI Agent free to use?

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Who published Codex CLI Agent?

richfrem (@richfrem) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Codex CLI Agent by richfrem — Agent Skill

Name: Codex CLI Agent
Rating: 4.2 (5 reviews)
Author: richfrem

Codex CLI Agent

Codex CLI sub-agent for dispatching tasks to OpenAI-compatible models via the `codex` binary. Use for code-focused tasks routed to GPT-5 Codex or any OpenAI-compatible endpoint. Part of the run_agent.py multi-LLM task router — cli=codex target.

richfrem da6e940 10 files · 3.1 KB Updated Sep 10, 2026

File contents

Identity: The Codex Sub-Agent Dispatcher (Standard: gpt-5-codex)

Dispatches bounded tasks to the Codex CLI (codex binary). Uses the run_agent.py task router with cli=codex.

[!IMPORTANT] Default model: gpt-5-codex. Requires OPENAI_API_KEY in environment. The codex binary must be on PATH.

Orchestration Pattern: `run_agent.py`

python ./scripts/run_agent.py \
  <PERSONA_FILE> <INPUT_FILE> <OUTPUT_FILE> "<INSTRUCTION>" \
  --cli codex --model gpt-5-codex

The prompt is piped to codex exec via stdin — not passed as a positional arg — to avoid OS ARG_MAX limits and process listing exposure.

Example

python ./scripts/run_agent.py \
  agents/refactor-expert.md \
  target.py \
  refactor.md \
  "Refactor this function and explain the top 3 changes." \
  --cli codex

With a different model

python ./scripts/run_agent.py \
  agents/security-auditor.md \
  target.py \
  security.md \
  "Find vulnerabilities. Rate severity: CRITICAL / MODERATE / MINOR." \
  --cli codex --model gpt-4o

When to Use codex-cli-agent

Use Case	Why codex
Code review / refactor	GPT-5 Codex is code-optimized
OpenAI endpoint routing	Use any `OPENAI_BASE_URL`-compatible target
Isolated sub-task to GPT-5	No main agent context bleed

Persona Registry (`agents/`)

Persona	Use For
`security-auditor.md`	Red team, vulnerability scanning
`refactor-expert.md`	Code optimization, DRY, readability
`architect-review.md`	System design, modularity

Smoke Test

echo "Say hello in one sentence." | codex exec --model gpt-5-codex -
python ./scripts/run_agent.py agents/refactor-expert.md target.py output.md "Summarize this file." --cli codex

Health Check

echo $OPENAI_API_KEY   # must be set
which codex            # must be on PATH
codex --version
codex exec --help      # verify exec subcommand and available flags

---name: codex-cli-agentdescription: Codex CLI sub-agent for dispatching tasks to OpenAI-compatible models via the `codex` binary. Use for code-focused tasks routed to GPT-5 Codex or any OpenAI-compatible endpoint. Part of the run_agent.py multi-LLM task router — cli=codex target.---## Identity: The Codex Sub-Agent Dispatcher (Standard: gpt-5-codex)Dispatches bounded tasks to the Codex CLI (`codex` binary). Uses the `run_agent.py` task router with `cli=codex`.> [!IMPORTANT]> **Default model: `gpt-5-codex`.** Requires `OPENAI_API_KEY` in environment. The `codex` binary must be on PATH.---## Orchestration Pattern: `run_agent.py````bashpython ./scripts/run_agent.py \ <PERSONA_FILE> <INPUT_FILE> <OUTPUT_FILE> "<INSTRUCTION>" \ --cli codex --model gpt-5-codex```The prompt is piped to `codex exec` via stdin — not passed as a positional arg — to avoid OS ARG_MAX limits and process listing exposure.### Example```bashpython ./scripts/run_agent.py \ agents/refactor-expert.md \ target.py \ refactor.md \ "Refactor this function and explain the top 3 changes." \ --cli codex```### With a different model```bashpython ./scripts/run_agent.py \ agents/security-auditor.md \ target.py \ security.md \ "Find vulnerabilities. Rate severity: CRITICAL / MODERATE / MINOR." \ --cli codex --model gpt-4o```---## When to Use codex-cli-agent| Use Case | Why codex ||----------|-----------|| Code review / refactor | GPT-5 Codex is code-optimized || OpenAI endpoint routing | Use any `OPENAI_BASE_URL`-compatible target || Isolated sub-task to GPT-5 | No main agent context bleed |---## Persona Registry (`agents/`)| Persona | Use For ||---------|---------|| `security-auditor.md` | Red team, vulnerability scanning || `refactor-expert.md` | Code optimization, DRY, readability || `architect-review.md` | System design, modularity |---## Smoke Test```bashecho "Say hello in one sentence." | codex exec --model gpt-5-codex -python ./scripts/run_agent.py agents/refactor-expert.md target.py output.md "Summarize this file." --cli codex```---## Health Check```bashecho $OPENAI_API_KEY # must be setwhich codex # must be on PATHcodex --versioncodex exec --help # verify exec subcommand and available flags```

Frequently asked questions