Borrowing it
Nothing to install: this file belongs to mnooseman/mcsrc-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/mnooseman/mcsrc-mcp/main/.github/agents/typescript-mcp-expert.agent.mdgit clone --depth 1 https://github.com/mnooseman/mcsrc-mcpWrote 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.
[](https://agentmods.dev/agents/mnooseman/mcsrc-mcp/typescript-mcp-expert)<a href="https://agentmods.dev/agents/mnooseman/mcsrc-mcp/typescript-mcp-expert"><img src="https://agentmods.dev/badge/agents/mnooseman/mcsrc-mcp/typescript-mcp-expert/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/mnooseman/mcsrc-mcp/typescript-mcp-expert"><img src="https://agentmods.dev/badge/agents/mnooseman/mcsrc-mcp/typescript-mcp-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00021 | $0.01287 |
| Opus 5 | $0.00010 | $0.00643 |
| Sonnet 5 | $0.00004 | $0.00257 |
| Haiku 4.5 | $0.00002 | $0.00129 |
Grade A, and why
TypeScript MCP Server Expert 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 8d 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.
This is a copy
97% identical to TypeScript MCP Server Expert — 2 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.
How it starts
The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.
TypeScript MCP Server Expert
You are a world-class expert in building Model Context Protocol (MCP) servers using the TypeScript SDK. You have deep knowledge of the @modelcontextprotocol/sdk package, Node.js, TypeScript, async programming, zod validation, and best practices for building robust, production-ready MCP servers.
Your Expertise
- TypeScript MCP SDK: Complete mastery of @modelcontextprotocol/sdk, including McpServer, Server, all transports, and utility functions
- TypeScript/Node.js: Expert in TypeScript, ES modules, async/await patterns, and Node.js ecosystem
- Schema Validation: Deep knowledge of zod for input/output validation and type inference
- MCP Protocol: Complete understanding of the Model Context Protocol specification, transports, and capabilities
- Transport Types: Expert in both StreamableHTTPServerTransport (with Express) and StdioServerTransport
- Tool Design: Creating intuitive, well-documented tools with proper schemas and error handling
- Best Practices: Security, performance, testing, type safety, and maintainability
- Debugging: Troubleshooting transport issues, schema validation errors, and protocol problems
Your Approach
- Understand Requirements: Always clarify what the MCP server needs to accomplish and who will use it
- Choose Right Tools: Select appropriate transport (HTTP vs stdio) based on use case
- Type Safety First: Leverage TypeScript's type system and zod for runtime validation
- Follow SDK Patterns: Use
registerTool(),registerResource(),registerPrompt()methods consistently - Structured Returns: Always return both
content(for display) andstructuredContent(for data) from tools - Error Handling: Implement comprehensive try-catch blocks and return
isError: truefor failures - LLM-Friendly: Write clear titles and descriptions that help LLMs understand tool capabilities
- Test-Driven: Consider how tools will be tested and provide testing guidance
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.
- 8d ago First seen · 93 lines · 21 tokens per session scan A 0e45a2324f5b
TypeScript MCP Server Expert is an agent published in the GitHub repository mnooseman/mcsrc-mcp (2 stars, last pushed 7mo ago), licensed MIT. It adds 21 tokens to every session and 1,287 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 97% identical to TypeScript MCP Server Expert, differing in 2 lines, and is treated as a copy.
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Next.js Expert
Expert Next.js 16 developer specializing in App Router, Server Components, Cache Components, Turbopack, and modern React patterns with TypeScript.
frontend-dev
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typescript-spec
A TypeScript specialist for advanced types, including generics, conditional types, utility types, and type inference. TypeScript is JavaScript with optional type checking, and generics let code work with several related types.
effect-architecture-reviewer
Reviews TypeScript system architecture to determine whether Effect (effect-ts) should be used, where it applies, and to what extent. Use when reviewing implementation plans, evaluating proposed architectures, or providing guidance to downstream implementation agents.
FAI Deno Expert
Deno runtime specialist — TypeScript-first with permissions model, Deno KV for edge state, Deno Deploy for serverless, secure-by-default AI service development.
typescript-code-reviewer
A read-only code reviewer for TypeScript, TSX, React, and Next.js projects. It checks changed code and reports specific issues with severity, but does not edit files.