wiki-qa — Claude Code skill: what it does, how to install
Answers codebase questions grounded strictly in source code, generating Mermaid diagrams and line-level citations.
npx skills add microsoft/skills --skill wiki-qa -a claude-codeWhat wiki-qa does
The skill forces the AI agent to ground every explanation strictly in source code files. Hallucinations or guesses are explicitly banned. First, the assistant inspects repository context via git remote get-url origin and gets the default branch using git rev-parse --abbrev-ref HEAD. If a remote host like GitHub or Azure DevOps exists, citations become clickable URLs pointing to exact line numbers. For purely local folders, it switches to file paths in parentheses.
Responses follow a strict format. The agent builds a Key Files table mapping files to roles and renders at least one Mermaid diagram whenever explaining architecture or data flow. If the repository lacks enough data to answer, the agent states that directly instead of guessing. Without access to local files and Git, resolving accurate citations will fail.
What it helps with
- navigate an unfamiliar codebase with line-level citations
- trace where a specific component or function is declared
- generate Mermaid diagrams of internal data flow directly from code
- document module responsibilities in a structured reference table
Example prompts for the agent
- How does the authentication flow work in this project?
- Where is the payment processing pipeline defined?
- Explain the data flow between services with a Mermaid diagram
How to install wiki-qa
1Skills CLI (Vercel)
npx skills add microsoft/skills --skill wiki-qa -a claude-code2Manually: put the files in place
~/.claude/skills/wiki-qa/SKILL.mdCopy the whole skill folder; for one project use .claude/skills/wiki-qa/
Manually: put the files in place
.agents/skills/wiki-qa/SKILL.mdFor all projects use ~/.agents/skills/
Manually: put the files in place
.cursor/skills/wiki-qa/SKILL.mdCursor also reads .agents/skills/ and .claude/skills/
1GitHub CLI
gh skill install microsoft/skills wiki-qa2Manually: put the files in place
.github/skills/wiki-qa/SKILL.mdPlatform CLI
gemini skills install https://github.com/microsoft/skills --path .github/plugins/deep-wiki/skills/wiki-qaManually: put the files in place
.devin/skills/wiki-qa/SKILL.mdThe legacy .windsurf/skills/ path still works
Claude.ai
Zip the folder and upload it in Settings → Capabilities → Skills
Step by step, with commands for each platform: How to install skills in Claude Code: five ways
Questions about wiki-qa
How to install wiki-qa in Claude Code?
Run npx skills add microsoft/skills --skill wiki-qa -a claude-code. Alternatively, place the skill definition file at ~/.claude/skills/wiki-qa/SKILL.md.
What does the wiki-qa skill do?
It guides the assistant to analyze repository files before answering codebase questions. The output includes verified line citations, structured component tables, and Mermaid architecture diagrams.
Why does wiki-qa run git commands before answering?
It checks git remote get-url origin and git rev-parse --abbrev-ref HEAD to format citations correctly. With a valid remote, it creates linked URLs to source files, while local-only repos fall back to file paths.
Source text
SKILL.md · MIT
--- name: wiki-qa description: Answers questions about a code repository using source file analysis. Use when the user asks a question about how something works, wants to understand a component, or needs help navigating the codebase. license: MIT metadata: author: Microsoft version: "1.0.0" --- # Wiki Q&A Answer repository questions grounded entirely in source code evidence. ## When to Activate - User asks a question about the codebase - User wants to understand a specific file, function, or component - User asks "how does X work" or "where is Y defined" ## Source Repository Resolution (MUST DO FIRST) Before answering any question, you MUST determine the source repository context: 1. **Check for git remote**: Run `git remote get-url origin` to detect if a remote exists 2. **Ask the user**: _"Is this a local-only repository, or do you have a source repository URL (e.g., GitHub, Azure DevOps)?"_ - Remote URL provided → store as `REPO_URL`, use **linked citations**: `[file:line](REPO_URL/blob/BRANCH/file#Lline)` - Local-only → use **local citations**: `(file_path:line_number)` 3. **Determine default branch**: Run `git rev-parse --abbrev-ref HEAD` 4. **Do NOT proceed** until source repo context is resolved ## Procedure 1. Resolve source repo context (see above) 2. Detect the language of the question; respond in the same language 3. Search the codebase for relevant files 4. Read those files to gather evidence 5. Synthesize an answer with inline linked citations ## Response Format - Use `##` headings, code blocks with language tags, tables, bullet lists - Cite sources inline using resolved format: - **Remote**: `[src/path/file.ts:42](REPO_URL/blob/BRANCH/src/path/file.ts#L42)` - **Local**: `(src/path/file.ts:42)` - Include a "Key Files" table mapping files to their roles (with linked citations in the "File" column) - **Include at least 1 Mermaid diagram** when the answer involves architecture, data flow, or relationships — a diagram makes the answer 10x more useful - **Use tables** for any structured data in the answer (component lists, API endpoints, config options, comparisons) - If information is insufficient, say so and suggest files to examine ## Rules - ONLY use information from actual source files - NEVER invent, guess, or use external knowledge - Think step by step before answering
© Microsoft · MIT · microsoft/skills
