nips/AD.md

NIP-AD

MCP Server and Skill Announcements

draft optional

Defines event kinds for announcing MCP servers and skills.

---

MCP Server Announcement (Kind 4200)

Announces an MCP server that provides tools to agents.

{
  "kind": 4200,
  "pubkey": "<publisher-pubkey>",
  "tags": [
    ["name", "<server-name>"],
    ["description", "<what-the-server-does>"],
    ["command", "<execution-command>"]
  ],
  "content": ""
}

Tags

• name — Server identifier
• description — What the server provides
• command — Command to start the server (e.g., npx @anthropic-ai/mcp-server-fetch)

---

Skill Announcement (Kind 4202)

Announces a skill—packaged capabilities with instructions and associated files.

{
  "kind": 4202,
  "pubkey": "<publisher-pubkey>",
  "tags": [
    ["title", "<skill-name>"],
    ["description", "<what-the-skill-does>"],
    ["e", "<1063-event-id>"],
    ["license", "<SPDX-identifier>"]
  ],
  "content": "<skill-instructions>"
}

Tags

• title — Skill name
• description — One-line description
• e — Reference to NIP-94 file metadata (kind 1063), one or more
• license — SPDX license identifier

Content

Contains skill instructions in markdown, injected into agent context when active.

Referenced Files

Each e tag references a kind 1063 event with:

• url — File location
• name — Relative filepath for installation
• m — MIME type
• x — SHA-256 hash