Skill Up for Codex

CommunitySkillDeveloper Tools

An evaluation and evolution tool for Agent Skills.

How to install Skill Up in Codex

In Codex, ask the built-in skill installer for it:

$skill-installer install the <skill> skill from https://github.com/alibaba/skill-up

Type this in Codex and replace <skill> with a folder name from 'What it contains'. $skill-installer is the skill installer built into Codex, and it downloads the skill from GitHub. Restart Codex if the skill doesn't show up. Check the repo README for any setup it needs. Source: Codex skills docs.

Or copy the skill folder (the one with SKILL.md) into ~/.agents/skills to use it in every project, or into .agents/skills in a repo to share it with that repo. Codex picks up new skills automatically. (where Codex loads skills)

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What it contains

Skills (21)

  • code-stats — Analyzes code files and reports statistics including line counts, file counts by extension, and total size. Use this skill whenever the user wants to understand the composition of a codebase - asking about "how many lines of code", "what file types exist"…
  • deepseek-harness — Decode the marker fixture used by the DeepSeek Harness integration example.
  • user-simulator — Ask for missing deployment settings and summarize the requested configuration without deploying it.
  • skill-upper — Capture and review Agent Skill observations, and create, run, diagnose, or iteratively improve Skill evaluations (evals) with the skill-up CLI. Use when the user asks to record explicitly attributed Skill usage or feedback; review observations or…
  • agent-judge-criteria — Reviews code and provides detailed quality assessment
  • custom-engine
  • expect-short-circuit — Quickly produces accurate calculation results when a user needs arithmetic, unit conversion, or mathematical formula solving. Triggered when users say things like "help me calculate", "compute", "how much is", etc.
  • file-and-tool-rules — Triggered when the user needs to organize project files, analyze directory structure, or generate a project report. Use MCP tools to read file contents and produce a structured organization report. Trigger phrases include "help me organize this project"…
  • full-report-pipeline — Triggered when the user submits code or requests a comprehensive code quality analysis. Automatically performs static analysis, code review, and quality scoring. Analysis covers coding standards, potential bugs, performance issues, and security…
  • git-context — Analyzes git repositories and commit history
  • mcp-case-overrides — Per-case mocked MCP override smoke skill used by skill-up e2e tests.
  • mcp-mocked-marker — MCP mocked marker smoke skill used by skill-up e2e tests.
  • mcp-stdio-marker — MCP stdio marker smoke skill used by skill-up e2e tests.
  • mock-engine
  • multi-turn-conversation — SDD-RIPER workflow executor with phase gating
  • multiturn-session
  • retry-and-parallelism — A skill with potentially flaky behavior for testing retry
  • sandbox-mcp — Verify Sandbox MCP can be installed and called from skill-up.
  • script-judge-eval — Triggered when the user needs to convert data formats, such as CSV to JSON, JSON to YAML, or XML to JSON. Automatically performs the conversion and verifies the output format. Trigger phrases include "convert format", "CSV to JSON", "help me convert this…
  • text-match-rules — Triggered when the user submits code or requests a code review. Automatically analyzes code quality, identifies potential bugs, security vulnerabilities, and performance issues, and provides improvement suggestions. Trigger phrases include "take a look at…
  • trigger-detection — Triggered when the user expresses boredom, low mood, frustration, irritation, or a need to relax. Responds with warm words of comfort and tells a joke to lighten the atmosphere. Trigger phrases include "I'm so bored", "feeling down", "so frustrated"…

About this listing

Skill Up is a community collection of agent skills on GitHub by alibaba: folders with a SKILL.md file, the format Codex loads skills from. Its README mentions Codex. It passed the CodexStacks quality filter for skills (at least 100 stars, pushed in the last 90 days, not a fork or a list, and at least one SKILL.md with a name and description). OpenAI hasn't reviewed it, but it passed our Codex install check on Oct 28, 2026 (an install and load check, not a code review). From its files we found 21 skills. It's one of 441 listings in the Developer Tools category (category assigned by CodexStacks from the repo's topics and description).

Skill Up FAQ

How do I install Skill Up in Codex?

In Codex, type $skill-installer install the <skill> skill from https://github.com/alibaba/skill-up. $skill-installer is the skill installer built into Codex (Codex skills docs). Or copy the skill folder (the one with SKILL.md) into ~/.agents/skills to use it in every project, or into .agents/skills in a repo to share it with that repo. Codex picks up new skills automatically.

Is Skill Up an official Codex skill?

No. Skill Up is a community repo on GitHub by alibaba. It passed the CodexStacks quality filter, but OpenAI hasn't reviewed it, but it passed our Codex install check on Oct 28, 2026 (an install and load check, not a code review), so read the code before you install it.

What does Skill Up include?

From its manifest and repo files, Skill Up includes 21 skills: code-stats, deepseek-harness, user-simulator, skill-upper, agent-judge-criteria, custom-engine….

Details

Type
Skill
Category
Developer Tools (assigned by us)
Source
Community
Author
alibaba
License
Apache-2.0
GitHub stars
1,392 (at last sync)
Last push
2026-10-29
GitHub topics
ai, ai-agents, alibaba
Source
https://github.com/alibaba/skill-up
Website
https://alibaba.github.io/skill-up/
Listed via
GitHub search: Codex skills (SKILL.md)
Install check by CodexStacks
Passed on Oct 28, 2026 with Codex CLI 0.163.0: Codex loaded its skills. proof · how we check

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Listed on CodexStacks

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[![Listed on CodexStacks](https://codexstacks.com/badge.svg)](https://codexstacks.com/p/skill-up/)

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<a href="https://codexstacks.com/p/skill-up/"><img src="https://codexstacks.com/badge.svg" alt="Listed on CodexStacks" width="172" height="28"></a>

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<a href="https://codexstacks.com/p/skill-up/" style="display:block;max-width:380px;box-sizing:border-box;padding:14px 16px;border:1px solid #3a2c26;border-radius:12px;background:#0d0b0a;color:#f3ece6;font:14px/1.45 -apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;text-decoration:none"><span style="display:block;font-size:16px;font-weight:700;color:#f3ece6">Skill Up</span><span style="display:block;margin:2px 0 8px;font-size:12px;color:#b5a9a1">Community Codex skill · 21 skills</span><span style="display:block;margin:0 0 10px;color:#ddd3cc">An evaluation and evolution tool for Agent Skills.</span><span style="font-size:12px;font-weight:600;color:#ffb347">View on CodexStacks →</span></a>

Markdown summary

**[Skill Up on CodexStacks](https://codexstacks.com/p/skill-up/)**: Community Codex skill with 21 skills.

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