typescript

Overview of typescript skill

What this typescript skill does

The typescript skill helps you work in TypeScript projects with a strict, reliability-first setup. It is aimed at people who want the assistant to respect tsconfig discipline, linting, and test coverage instead of generating loose code that compiles only by accident. If you need a practical typescript guide for editing real code, this skill is a better fit than a generic prompt because it encodes project structure, tooling expectations, and failure-prevention habits.

Who should use it

Use this typescript skill when you are editing .ts or .tsx files, tightening type safety, or adding new code that must pass eslint, tsc, and jest. It is especially useful in repos that already rely on strict compiler settings and want changes to fit the existing architecture rather than bypass it.

Main differentiators

The key value is not “write TypeScript” in the abstract, but “write TypeScript that survives strict checks.” The skill centers strict mode, clear separation between core logic and side effects, and required tooling like typecheck and tests. That makes it a good typescript for Code Editing option when correctness and maintainability matter more than quick scaffolding.

How to Use typescript skill

Install and activate it

For typescript install, add the skill to your Claude skills setup, then work in a repository that matches the path filters for **/*.ts, **/*.tsx, and tsconfig*.json. The skill is not user-invocable in the repo metadata, so it is meant to activate from file context rather than by command. In practice, that means you open or mention TypeScript files and let the assistant apply the skill while editing.

Give the skill the right input

A strong prompt should include the goal, the file being changed, the existing pattern to follow, and the constraint that matters most. For example: “Update src/core/services/calculatePrice.ts to support a discount code, keep strict null checks, preserve pure logic in core, and add a Jest test for the new branch.” This is better than “fix this TypeScript file” because it tells the skill what success looks like and what not to break.

Read these files first

Start with SKILL.md, then inspect tsconfig.json, package.json, eslint.config.js, and CLAUDE.md if present. Those files tell you whether strict mode is truly enforced, which scripts are expected to pass, and how the repo organizes business logic versus infrastructure. If the project has no supporting files, treat the skill as a policy prompt and verify the real constraints before making edits.

Workflow that produces better edits

Use a three-step loop: understand the local pattern, make the smallest safe change, then validate against typecheck and tests. Keep new domain logic in pure functions when possible, and push I/O, network calls, and database access into infrastructure layers. If the change touches public types, update tests alongside code so the assistant does not optimize for compilation only.

typescript skill FAQ

Is this better than a normal prompt?

Yes, when the task depends on strict typing, existing structure, or predictable validation. A normal prompt may produce valid-looking code, but the typescript skill is tuned to keep the assistant inside compiler and lint boundaries. If you only need a one-off snippet, the skill is probably overkill.

Do I need to be a TypeScript expert to use it?

No. Beginners can use it well if they provide a concrete file target and a clear outcome. The main mistake is asking for “clean up my TypeScript” without saying whether the priority is types, tests, architecture, or a specific bug.

When should I not use it?

Skip it if the repository is not TypeScript-based, if the change is mostly design work, or if you are prototyping code that will be thrown away. It is also a poor fit when the repo does not use tsc, ESLint, or Jest, because the skill’s advice assumes those checks exist and matter.

How does it fit the wider toolchain?

It fits best in repos where code editing is validated by compiler output, lint rules, and tests. If your stack uses additional constraints such as build pipelines, generated types, or framework-specific conventions, mention them up front so the skill can respect them instead of guessing.

How to Improve typescript skill

Give stricter context, not more words

The best improvement is specificity. Tell the assistant which module is authoritative, what files are safe to edit, and which behavior must remain unchanged. For example, “Change only src/infra/api/user.ts, keep the handler signature stable, and add tests in tests/integration/user.test.ts.”

Watch for the common failure modes

The most common misses are overusing any, moving side effects into pure layers, and making a change that passes syntax but fails tsc or Jest. Another frequent problem is editing the wrong abstraction level: a domain rule belongs in core, not in an API handler or utility just because it is convenient.

Iterate from compiler and test feedback

After the first pass, improve the request using real errors from tsc, ESLint, or test output. Paste the exact error, the file path, and the intended design direction, then ask for the minimal fix. This gives the typescript skill enough signal to correct the issue without rewriting unrelated code.

Ask for structure-aware output

If you want better results from typescript for Code Editing, ask for changes that respect project boundaries: pure functions for business logic, explicit types for public APIs, and tests that cover edge cases rather than only happy paths. That produces code that is easier to review, easier to validate, and less likely to regress when the repo gets stricter.