mattpocock/skills

Name: mattpocock/skills (Claude Skill)
Author: mattpocock

Why use it

Key features

TypeScript idioms from a recognized TS expert
Opinionated testing approach (colocate, integration-first)
Refactoring patterns that favor type-safety preservation
Workflow skills — commit style, PR descriptions, etc.
MIT licensed

Live Demo

What it looks like in practice

ready

Install

Author repository · Claude Skills documentation

Use Cases

Real-world ways to use mattpocock/skills

Apply Matt's TS patterns to an existing project

👤 TypeScript devs upgrading code quality ⏱ ~90 min intermediate

When to use: Your project has anys and shrug-worthy types and you want a principled cleanup.

Flow

Scan

Use mattpocock/ts-review. Scan /src and list every any, every unsafe cast, every type hole. Group by file.✓ Copied

→ Itemized findings, not a summary
Fix with principles

Fix the top 20, narrowest fix per case. Respect Matt's "prefer inference" rule — don't explicit-annotate what TS can infer.✓ Copied

→ Minimal diffs, type-safety gained
Check

Run tsc --noEmit. Any regressions?✓ Copied

→ Clean compile or precisely-scoped remaining items

Outcome: A measurably more type-safe codebase following a principled methodology.

Pitfalls

Skill applies Matt's opinions where your team disagrees (e.g. interface vs type) — Override with "skip the interface-vs-type conversion, keep existing style"

Combine with: filesystem

Build a feature test-first, Matt's way

👤 Devs adopting a more test-forward workflow ⏱ ~60 min intermediate

When to use: You have a new feature to build and want to try test-first with modern TS tooling.

Flow

Write the test

Use mattpocock/test-first. I want to add a parseInvoice function. Write the test (vitest, integration-over-unit bias) before any impl.✓ Copied

→ Failing test with realistic fixtures
Implement

Now the minimal implementation. Type-safe, no any.✓ Copied

→ Green test with clean types
Refactor

Apply refactor patterns from the skill — extract helpers if they earn it, no premature abstraction.✓ Copied

→ Refactor only where the skill's criteria are met

Outcome: A test suite that tests behavior, an impl that satisfies it, and restraint on the refactor.

Pitfalls

Opinions collide with team's existing Jest setup — Ask the skill to adapt — it's opinionated but can be reoriented

Combine with: filesystem

Combinations

Pair with other MCPs for X10 leverage

mattpocock-skills-skill + filesystem

Apply to a full repo

Run ts_review over the whole /src tree and report.✓ Copied

mattpocock-skills-skill + github

Open a PR per review

For the top 3 cleanups, create one PR each with a clear description.✓ Copied

Tools

What this MCP exposes

Tool	Inputs	When to call
ts_review	path	TS-specific audit
test_first	feature_spec	Starting a new feature
refactor_with_types	path, goal	Type-preserving refactor

Cost & Limits

What this costs to run

API quota: N/A
Tokens per call: Review-heavy — budget for big reads on large codebases
Monetary: Free
Tip: Scope by directory first; don't scan everything

Security

Permissions, secrets, blast radius

Minimum scopes: filesystem-read

Credential storage: None

Data egress: None

Troubleshooting

Common errors and fixes

Skill feels too opinionated

That's the point — override specific opinions in your prompt, or fork and edit

Recommendations conflict with team style

Share the output with the team; use it as a discussion starter, not a mandate

Doesn't know my niche library

Skills are TS-general — prepend your library's docs to the context

Alternatives