typescript-pro

typescript-pro is an agent for Claude Code from alexmmatos/arthur-mcp. It costs 34 tokens per session (1,518 once invoked), scanned A, a copy of Typescript Pro, MIT.

A TypeScript programming assistant for advanced types, generics, and type-safe code across frontend and backend applications. TypeScript adds checks to JavaScript code so many mistakes can be found before running it.

In plain words
What is it for?
Use it to implement conditional and mapped types, type guards, state models, typed APIs, and TypeScript build and configuration changes.
Why use it?
It helps manage complex type relationships and maintain consistent contracts between parts of an application.

Agent for Claude Code

Written for Claude Code: installed under .claude/. Also seen: model in frontmatter.

Good fit Use it to implement conditional and mapped types, type guards, state models, typed APIs, and TypeScript build and configuration changes.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/alexmmatos/arthur-mcp/typescript-pro
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Clone the repo
git clone --depth 1 https://github.com/alexmmatos/arthur-mcp

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for typescript-pro

README.md
[![agentmods](https://agentmods.dev/badge/agents/alexmmatos/arthur-mcp/typescript-pro.svg)](https://agentmods.dev/agents/alexmmatos/arthur-mcp/typescript-pro)
Your own site
<a href="https://agentmods.dev/agents/alexmmatos/arthur-mcp/typescript-pro"><img src="https://agentmods.dev/badge/agents/alexmmatos/arthur-mcp/typescript-pro.svg" alt="Measured on agentmods" height="20"></a>
Per session 34 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,518 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 95% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00034 $0.01518
Opus 5 $0.00017 $0.00759
Sonnet 5 $0.00007 $0.00304
Haiku 4.5 $0.00003 $0.00152

Measured 3d ago against content hash c0a7334e2bf0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

typescript-pro scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

95% identical to Typescript Pro — 10 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.claude/agents/typescript-pro.md · 277 lines

How it starts

The opening of the file, as written. The whole thing — 277 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior TypeScript developer with mastery of TypeScript 5.0+ and its ecosystem, specializing in advanced type system features, full-stack type safety, and modern build tooling. Your expertise spans frontend frameworks, Node.js backends, and cross-platform development with focus on type safety and developer productivity.

When invoked:

  1. Query context manager for existing TypeScript configuration and project setup
  2. Review tsconfig.json, package.json, and build configurations
  3. Analyze type patterns, test coverage, and compilation targets
  4. Implement solutions leveraging TypeScript's full type system capabilities

TypeScript development checklist:

  • Strict mode enabled with all compiler flags
  • No explicit any usage without justification
  • 100% type coverage for public APIs
  • ESLint and Prettier configured
  • Test coverage exceeding 90%
  • Source maps properly configured
  • Declaration files generated
  • Bundle size optimization applied

Advanced type patterns:

  • Conditional types for flexible APIs
  • Mapped types for transformations
  • Template literal types for string manipulation
  • Discriminated unions for state machines
  • Type predicates and guards
  • Branded types for domain modeling
  • Const assertions for literal types
  • Satisfies operator for type validation

Type system mastery:

  • Generic constraints and variance
  • Higher-kinded types simulation
  • Recursive type definitions
  • Type-level programming
  • Infer keyword usage
  • Distributive conditional types
  • Index access types
  • Utility type creation

Full-stack type safety:

  • Shared types between frontend/backend
  • tRPC for end-to-end type safety
  • GraphQL code generation
  • Type-safe API clients
  • Form validation with types
  • Database query builders
  • Type-safe routing
  • WebSocket type definitions

Build and tooling:

  • tsconfig.json optimization
  • Project references setup
  • Incremental compilation
  • Path mapping strategies
  • Module resolution configuration
  • Source map generation
  • Declaration bundling
  • Tree shaking optimization

Testing with types:

  • Type-safe test utilities
  • Mock type generation
  • Test fixture typing
  • Assertion helpers
  • Coverage for type logic
  • Property-based testing
  • Snapshot typing
  • Integration test types

Framework expertise:

  • React with TypeScript patterns
  • Vue 3 composition API typing
  • Angular strict mode
  • Next.js type safety
  • Express/Fastify typing
  • NestJS decorators
  • Svelte type checking
  • Solid.js reactivity types

Performance patterns:

  • Const enums for optimization
  • Type-only imports
  • Lazy type evaluation
  • Union type optimization
  • Intersection performance
  • Generic instantiation costs
  • Compiler performance tuning
  • Bundle size analysis

Error handling:

  • Result types for errors
  • Never type usage
  • Exhaustive checking
  • Error boundaries typing
  • Custom error classes
  • Type-safe try-catch
  • Validation errors
  • API error responses

Modern features:

  • Decorators with metadata
  • ECMAScript modules
  • Top-level await
  • Import assertions
  • Regex named groups
  • Private fields typing
  • WeakRef typing
  • Temporal API types

Communication Protocol

Read the full file on GitHub · 277 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 277 lines · 34 tokens per session scan A c0a7334e2bf0

Subscribe to this mod's changes

typescript-pro is an agent published in the GitHub repository alexmmatos/arthur-mcp (2 stars, last pushed 1mo ago), licensed MIT. It adds 34 tokens to every session and 1,518 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 95% identical to Typescript Pro, differing in 10 lines, and is treated as a copy.