Agent Skill
Source Driven Development skill
source-driven-developmentaddyosmani/agent-skillsskills/source-driven-development/SKILL.md
Grounds every implementation decision in official documentation. Use when you want to verify an approach against the official docs before implementing it, or when you want authoritative, source-cited code free from outdated patterns. Use when building with any framework or library where correctness matters.
always on
55 tokname + description
once used
2,023 tokSKILL.md body
bundled files
0
repo stars
109kGitHub
Install the Source Driven Development skill
Skills CLI (Claude Code, Codex, Cursor and others)
npx skills add https://github.com/addyosmani/agent-skills --skill source-driven-development
Claude Code, by hand (all projects)
git clone --depth 1 https://github.com/addyosmani/agent-skills.git /tmp/agent-skills mkdir -p ~/.claude/skills cp -R /tmp/agent-skills/skills/source-driven-development ~/.claude/skills/source-driven-development
For one project only, copy the folder into .claude/skills/ in that project instead. The agent picks it up when a task matches its description.
What it costs your context
Agent Skills load in three steps. Tokens counted with the o200k tokenizer; your model's count will differ a little.
| When | What loads | Cost |
|---|---|---|
| Every session | Name and description | 55 tok |
| When the agent uses it | The SKILL.md instructions | 2,023 tok |
| Only if opened | No bundled files | — |
Until it is used, source-driven-development costs about 25× less than the median MCP server we measured (1,362 tokens on every turn). Installing all 25 skills from addyosmani/agent-skills would load 1,829 tokens of descriptions. Skills vs MCP study
Checks
Our checks found nothing to flag: it follows the Agent Skills specification's naming and size guidelines and doesn't pipe downloads into a shell.
Checked 2026-10-22 · method
What's inside
The headings of its SKILL.md. Read the full file on GitHub.
- Source-Driven Development
- Overview
- When to Use
- The Process
- Step 1: Detect Stack and Versions
- Step 2: Fetch Official Documentation
- Step 3: Implement Following Documented Patterns
- Step 4: Cite Your Sources
- Common Rationalizations
- Red Flags
- Verification
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