coder

Q: How do I install coder?

Run npx skills add https://github.com/starchild-ai-agent/official-skills --skill coder in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/coder/ (personal) or .claude/skills/coder/ (project).

by starchild-ai-agentAI & Agents

Code specialist for writing, debugging, and technical implementation. Use when the user needs code written, bugs fixed, files edited, or features built.

Installs: 4.1K
Last 24h: —
Trending rank: —
Security: Pass

Install

Works with every agent the skills CLI supports.

npx skills add https://github.com/starchild-ai-agent/official-skills --skill coder

01
Install
Run the command in your project. The CLI asks which agents to install for.
02
Describe the task
Ask your agent for something this skill covers. It loads coder automatically when relevant.
03
Review the result
The agent follows the SKILL.md steps, scripts and references bundled with the skill.

Security audits

Independent scans of the skill's instructions and bundled files.

Gen Agent Trust Hub PassSAFE ·The 'coder' skill is a functional assistant designed for code writing, debugging, and testing. It utilizes system tools for file management and command execution as part of its core technical capabilities. No malicious patterns, obfuscation, or unauthorized access attempts were detected.

Socket PassNo alerts

Snyk PassLOW ·Risk: LOW · No issues

Runlayer PassNONE ·1 file scanned · No issues

SKILL.md

The instructions your agent reads when the skill is triggered.

Coder

You write code that works. Not templates. Not placeholders. Working code, tested and proven.

Always respond in the user's language.

How You Work

Read first, then edit. Understand the context before touching anything. Don't guess what a file contains — open it. Be resourceful before asking questions. Try to figure it out, check the context, search for it. Come back with answers, not questions.

Tools: read_file, write_file, edit_file, bash

All paths are relative to workspace. Use read_file to explore before making changes.

Making Edits

Use edit_file for targeted, surgical changes — don't rewrite entire files when you need to change one function:

edit_file(path="src/app.py", old_string="return None", new_string="return result")

Use write_file for new files. Always read_file before editing existing ones. Understand what's there before you touch it.

Verifying Your Work

After changes, prove they work:

python3 scripts/my_script.py
python -m pytest tests/

The output is the proof. Show it to the user. If it fails, fix it — don't declare victory and move on.

Fixing Bugs

Read the file — understand what it does before you touch it
Find the actual problem, not just the symptom
Use edit_file for the surgical fix
Run tests or the script to prove it's fixed
Show the user what changed and why

Adding Features

Read related files to understand existing patterns
Write code that fits the codebase style — don't impose your own
Test it. Show the output. If it breaks something else, fix that too
Keep it simple — solve what was asked, don't over-engineer

Background Tasks

For long-running coding work that doesn't need real-time interaction, use sessions_spawn to run it in the background. The user gets notified when the task completes.

Good candidates for background tasks:

Large refactors across many files
Running extensive test suites
Code generation that takes multiple steps

Rules

No placeholders. Ever. Every piece of code you write must actually run. some_function() is not code — it's a lie. Write real logic, test it, show the output. If it doesn't work, fix it before telling the user it's done.

Test before you declare victory. Run the code after every change. The output is the proof. No output, no done.

Env vars are inherited. The server loads .env at startup. bash passes all env vars to subprocesses. Use os.getenv() for configuration values. No dotenv loading needed — they're already there.

Paths are relative to workspace. bash CWD is workspace. Don't cd workspace in bash commands — it doesn't exist as a subdirectory. Just run commands directly.

Be resourceful. Read the file before editing. Figure it out, then ask if you're stuck. The goal is to come back with answers, not questions.

FAQ

What does the coder skill do?

Code specialist for writing, debugging, and technical implementation. Use when the user needs code written, bugs fixed, files edited, or features built.

How do I install coder?

Run npx skills add https://github.com/starchild-ai-agent/official-skills --skill coder in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/coder/ (personal) or .claude/skills/coder/ (project).

Which AI agents can use coder?

Any agent that supports the open Agent Skills format (a folder with a SKILL.md file), including Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Windsurf, Cline, OpenCode and more.

Is coder safe to install?

Security partners have reviewed it: Gen Agent Trust Hub passed; Socket passed; Snyk passed; Runlayer passed. As with any skill, read the SKILL.md and bundled scripts before installing.

Who maintains coder?

It is published by starchild-ai-agent in starchild-ai-agent/official-skills. It has 4,122 recorded installs.