Librarian Skill
Deep codebase exploration across remote repositories.
How to Use This Skill
Reference Structure
| File | Purpose | When to Read |
|---|---|---|
tool-routing.md | Tool selection decision trees | Always read first |
opensrc-api.md | API reference, types | Writing opensrc code |
opensrc-examples.md | JavaScript patterns, workflows | Implementation examples |
linking.md | GitHub URL patterns | Formatting responses |
diagrams.md | Mermaid patterns | Visualizing architecture |
Reading Order
- •Start with
tool-routing.md→ choose tool strategy - •If using opensrc:
- •Read
opensrc-api.mdfor API details - •Read
opensrc-examples.mdfor patterns
- •Read
- •Before responding:
linking.md+diagrams.mdfor output formatting
Tool Arsenal
| Tool | Best For | Limitations |
|---|---|---|
| grep_app | Find patterns across ALL public GitHub | Literal search only |
| context7 | Library docs, API examples, usage | Known libraries only |
| opensrc | Fetch full source for deep exploration | Must fetch before read |
Quick Decision Trees
"How does X work?"
code
Known library? ├─ Yes → context7.resolve-library-id → context7.query-docs │ └─ Need internals? → opensrc.fetch → read source └─ No → grep_app search → opensrc.fetch top result
"Find pattern X"
code
Specific repo? ├─ Yes → opensrc.fetch → opensrc.grep → read matches └─ No → grep_app (broad) → opensrc.fetch interesting repos
"Explore repo structure"
code
1. opensrc.fetch(target) 2. opensrc.tree(source.name) → quick overview 3. opensrc.files(source.name, "**/*.ts") → detailed listing 4. Read: README, package.json, src/index.* 5. Create architecture diagram (see diagrams.md)
"Compare X vs Y"
code
1. opensrc.fetch(["X", "Y"])
2. Use source.name from results for subsequent calls
3. opensrc.grep(pattern, { sources: [nameX, nameY] })
4. Read comparable files, synthesize differences
Critical: Source Naming Convention
After fetching, always use source.name for subsequent calls:
javascript
const [{ source }] = await opensrc.fetch("vercel/ai");
const files = await opensrc.files(source.name, "**/*.ts");
| Type | Fetch Spec | Source Name |
|---|---|---|
| npm | "zod" | "zod" |
| npm scoped | "@tanstack/react-query" | "@tanstack/react-query" |
| pypi | "pypi:requests" | "requests" |
| crates | "crates:serde" | "serde" |
| GitHub | "vercel/ai" | "github.com/vercel/ai" |
| GitLab | "gitlab:org/repo" | "gitlab.com/org/repo" |
When NOT to Use opensrc
| Scenario | Use Instead |
|---|---|
| Simple library API questions | context7 |
| Finding examples across many repos | grep_app |
| Very large monorepos (>10GB) | Clone locally |
| Private repositories | Direct access |
Output Guidelines
- •Comprehensive final message - only last message returns to main agent
- •Parallel tool calls - maximize efficiency
- •Link every file reference - see
linking.md - •Diagram complex relationships - see
diagrams.md - •Never mention tool names - say "I'll search" not "I'll use opensrc"