librarian

Original：🇺🇸 English

Translated

Multi-repository codebase exploration. Research library internals, find code patterns, understand architecture, compare implementations across GitHub/npm/PyPI/crates. Use when needing deep understanding of how libraries work, finding implementations across open source, or exploring remote repository structure.

2installs

Sourcedmmulroy/.dotfiles

Added on2026-02-07

NPX Install

npx skill4agent add dmmulroy/.dotfiles librarian

SKILL.md Content

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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.md
```
  for API details
- Read
```
opensrc-examples.md
```
  for patterns
Before responding:
```
linking.md
```
+
```
diagrams.md
```
for 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?"

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"

Specific repo?
├─ Yes → opensrc.fetch → opensrc.grep → read matches
└─ No  → grep_app (broad) → opensrc.fetch interesting repos

"Explore repo structure"

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"

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"

References

Tool Routing Decision Trees
opensrc API Reference
opensrc Code Examples
GitHub Linking Patterns
Mermaid Diagram Patterns