Add NIP-AD: MCP Server and Skill Announcements

AD.md

@@ -0,0 +1,73 @@
+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.
+
+```json
+{
+  "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.
+
+```json
+{
+  "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