Copilot-Skills mcp-builder.instructions.md

Copilot-Skills mcp-builder.instructions.md is an instructions file for GitHub Copilot from TheSethRose/Copilot-Skills. It costs 1,705 tokens per session, scanned A, original, MIT.

Instructions for building MCP servers, which provide tools that an AI agent can call to use data or services. They cover agent-focused tool design and integrations such as APIs, FastMCP, Python, and TypeScript.

In plain words
What is it for?
Use them when designing agent tools, building an MCP server, connecting an API, or implementing an MCP integration in Python or TypeScript.
Why use it?
They help turn an external service into clear, useful agent actions with validated inputs and understandable errors.

Instructions file for GitHub Copilot

Written for GitHub Copilot: a Copilot chat mode or prompt.

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.

agentmods
npx agentmods add instructions/thesethrose/copilot-skills/mcp-builder
Clone the repo
git clone --depth 1 https://github.com/TheSethRose/Copilot-Skills

Made for: GitHub Copilot.

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 Copilot-Skills mcp-builder.instructions.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/mcp-builder.svg)](https://agentmods.dev/instructions/thesethrose/copilot-skills/mcp-builder)
Your own site
<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/mcp-builder"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/mcp-builder.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,705 This file is loaded in full into every session.
When invoked 1,705 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found 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 $0.01705 $0.01705
Opus 5 $0.00852 $0.00852
Sonnet 5 $0.00341 $0.00341
Haiku 4.5 $0.00170 $0.00170

Measured 6d ago against content hash 26435b798042, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

Copilot-Skills mcp-builder.instructions.md 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 6d 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.

.github/instructions/mcp-builder.instructions.md · 278 lines

How it starts

The opening of the file, as written. The whole thing — 278 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MCP Builder - Automatic Context Instructions

Related Prompt: /mcp-builder
Related Skill: .github/copilot-skills/mcp-builder/README.md

Triggers: mcp, model context protocol, mcp server, agent tools, llm integration, api integration, fastmcp, tool design

Context: MCP Server Development

When working with MCP-related files or when user queries contain MCP server keywords, this context is automatically activated.

Default Behaviors

When user mentions "mcp server" or "build mcp"

  1. Suggest /mcp-builder skill prompt
  2. Load agent-centric design principles
  3. Reference framework-specific documentation
  4. Use evaluation-driven development approach

When user mentions "tool design" or "agent tools"

  1. Focus on workflow-oriented tools (not just API wrappers)
  2. Optimize for context efficiency
  3. Design actionable error messages
  4. Follow natural task subdivisions

When user mentions "python mcp" or "fastmcp"

  1. Load Python-specific patterns
  2. Reference FastMCP or Python SDK documentation
  3. Use Pydantic for input validation
  4. Follow Python project structure conventions

When user mentions "typescript mcp" or "node mcp"

  1. Load TypeScript-specific patterns
  2. Reference MCP TypeScript SDK documentation
  3. Use Zod for input validation
  4. Follow Node/TypeScript project conventions

Quality Guidelines

✅ Do

  • Build workflow tools, not just API endpoint wrappers
  • Consolidate related operations into single tools
  • Return high-signal information (concise by default)
  • Use human-readable identifiers (names over IDs)
  • Design actionable, educational error messages
  • Validate all inputs with schemas (Pydantic/Zod)
  • Handle rate limiting and pagination gracefully
  • Test with realistic agent scenarios
  • Provide configurable detail levels (concise/detailed)
  • Keep responses under 25,000 tokens
  • Group related tools with consistent prefixes

❌ Don't

  • Simply wrap API endpoints without workflow consideration
  • Return exhaustive data dumps (respect context limits)
  • Use cryptic error messages
  • Skip input validation
  • Ignore rate limits or pagination
  • Hard-code configuration values
  • Mix workflow concerns in single tool
  • Create tools with unclear purposes
  • Return massive unformatted responses
  • Use technical IDs when names are available

Read the full file on GitHub · 278 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. 6d ago First seen · 278 lines · 1,705 tokens per session scan A 26435b798042

Subscribe to this mod's changes

Copilot-Skills mcp-builder.instructions.md is an instructions file published in the GitHub repository TheSethRose/Copilot-Skills (3 stars, last pushed 9mo ago), licensed MIT. It adds 1,705 tokens to every session, about $0.0085 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other instructions, from other repositories