MCP Server Builder skill for Claude and Codex

MCP Server Builder as an AI skill. It asks for Service or data to expose, Language and SDK, Transport and 3 more, then does the rest. Free to install in…

Install it once and Claude or Codex runs it for you. When your request matches, your AI loads the skill, asks for anything it is missing, and works through the template itself. Prefer to fill it in by hand? See the full prompt template.

Download the skill (.zip) · View SKILL.md

When it is used

Use when a service or dataset needs to be exposed to AI agents through a new MCP server with well-designed tools, schemas, auth, and tests. Do not use for using an existing MCP server or building a non-MCP plugin system. Related topics: AI, coding.

What it will ask you for

• Service or data to expose (longer free text)
• Language and SDK (choose one: TypeScript, Python, Go, Other)
• Transport (choose one: stdio, Streamable HTTP)
• Authentication (choose one: None, API key, OAuth, Per-user token)
• Read-only (choose one: Yes, No)
• Key operations (longer free text)

How it works

1. Group the key operations into a small set of task-shaped tools instead of mirroring every API endpoint.
2. Write each tool name, a description saying when to use it, and a typed input schema with described fields.
3. Shape tool results to be compact, paginated, and readable, and write errors that say what failed and what to try next.
4. Add authentication, secret handling, and confirmation inputs for destructive tools, honouring the read-only setting.
5. Produce the server code, ten multi-call evaluation questions with expected answers, and a test plan using an inspector.

What you get

The server code, a tool table with name, purpose, and schema, ten evaluation questions with expected answers, and a short test plan.

What it watches out for

• Exposing one tool per endpoint, which gives the agent forty similar choices and confuses selection.
• Returning whole raw API responses that flood the context window with fields the task never needs.
• Writing errors like Bad Request, which leave the agent no way to recover.

How to install

Claude.ai and the Claude desktop app

1. Download the skill .zip.
2. Open Settings, then Capabilities, and find Skills.
3. Choose Upload skill and select the .zip.
4. Ask Claude for help with the task. It loads the skill when your request matches.

Claude Code

1. Download the skill .zip.
2. Unzip it into ~/.claude/skills/ (or .claude/skills/ inside a project).
3. Start a new session. Claude Code loads the skill when your request matches.

Codex

1. Download the skill .zip.
2. Unzip it into ~/.agents/skills/ (or .agents/skills/ inside a project).
3. Codex picks it up on its own. Type $ and the skill name to use it, or just ask for the task.

Cursor

1. Download the Cursor rule (.mdc).
2. Save it in .cursor/rules/ inside your project.
3. Cursor's agent applies the rule when your request matches its description.

AGENTS.md (Codex, Cursor, and other coding agents)

1. Copy the AGENTS.md section.
2. Paste it into AGENTS.md at the root of your repository, creating the file if needed.
3. Coding agents that read AGENTS.md follow it when your request fits.