Add MCP sdtio interface

.changeset/cuddly-dragons-give.md

@@ -0,0 +1,5 @@
+---
+"nostrudel-bakery": minor
+---
+
+Add MCP sdtio interface

package.json

@@ -10,6 +10,7 @@
     "prepack": "pnpm build",
     "start": "node .",
     "dev": "nodemon --loader @swc-node/register/esm src/index.ts",
+    "mcp": "mcp-inspector node . --mcp --port 8080",
     "build": "tsc",
     "test": "vitest run",
     "format": "prettier -w ."
@@ -26,6 +27,7 @@
   "license": "MIT",
   "dependencies": {
     "@diva.exchange/i2p-sam": "^5.4.2",
+    "@modelcontextprotocol/sdk": "^1.8.0",
     "@noble/hashes": "^1.7.1",
     "@satellite-earth/core": "^0.5.0",
     "applesauce-core": "^0.11.0",
@@ -58,10 +60,12 @@
     "streamx": "^2.22.0",
     "unique-names-generator": "^4.7.1",
     "web-push": "^3.6.7",
-    "ws": "^8.18.1"
+    "ws": "^8.18.1",
+    "zod": "^3.24.2"
   },
   "devDependencies": {
     "@changesets/cli": "^2.28.1",
+    "@modelcontextprotocol/inspector": "^0.7.0",
     "@swc-node/register": "^1.10.9",
     "@swc/core": "^1.10.18",
     "@types/better-sqlite3": "^7.6.12",

src/app/index.ts

@@ -46,7 +46,7 @@ import secrets from "../services/secrets.js";
 import config from "../services/config.js";
 import logStore from "../services/log-store.js";
 import stateManager from "../services/state.js";
-import sqliteEventStore from "../services/event-cache.js";
+import eventCache from "../services/event-cache.js";
 import { inboundNetwork, outboundNetwork } from "../services/network.js";
 import { server } from "../services/server.js";
 import { SQLiteEventStore } from "../sqlite/event-store.js";
@@ -156,7 +156,7 @@ export default class App extends EventEmitter<EventMap> {
     });
 
     // Initialize the event store
-    this.eventStore = sqliteEventStore;
+    this.eventStore = eventCache;
 
     // setup decryption cache
     this.decryptionCache = new DecryptionCache(this.database.db);

src/args.ts

@@ -0,0 +1,12 @@
+import { parseArgs, ParseArgsConfig } from "node:util";
+
+const config = {
+  options: {
+    mcp: { type: "boolean" },
+    port: { type: "string", short: "p" },
+  },
+} as const satisfies ParseArgsConfig;
+
+const args = parseArgs(config);
+
+export default args;

src/env.ts

@@ -1,16 +1,17 @@
 import "dotenv/config";
 import { mkdirp } from "mkdirp";
-import { OUTBOUND_PROXY_TYPES } from "./const.js";
-
-import { normalizeToHexPubkey } from "./helpers/nip19.js";
 import { normalizeURL } from "applesauce-core/helpers";
 
+import { OUTBOUND_PROXY_TYPES } from "./const.js";
+import { normalizeToHexPubkey } from "./helpers/nip19.js";
+import args from "./args.js";
+
 export const OWNER_PUBKEY = process.env.OWNER_PUBKEY ? normalizeToHexPubkey(process.env.OWNER_PUBKEY) : undefined;
 export const PUBLIC_ADDRESS = process.env.PUBLIC_ADDRESS;
 export const DATA_PATH = process.env.DATA_PATH || "./data";
 await mkdirp(DATA_PATH);
 
-export const PORT = parseInt(process.env.PORT ?? "") || 3000;
+export const PORT = parseInt(args.values.port ?? process.env.PORT ?? "") || 3000;
 
 // I2P config
 export const I2P_PROXY = process.env.I2P_PROXY;
@@ -36,3 +37,5 @@ export const COMMON_CONTACT_RELAYS = process.env.COMMON_CONTACT_RELAYS
   : ["wss://purplepag.es", "wss://user.kindpag.es"].map(normalizeURL);
 
 export const IS_DEV = process.env.NODE_ENV === "development";
+
+export const IS_MCP = args.values.mcp;

src/helpers/nip19.ts

@@ -1,12 +1,15 @@
 import { getPubkeyFromDecodeResult, isHexKey } from "applesauce-core/helpers";
 import { nip19 } from "nostr-tools";
 
-export function normalizeToHexPubkey(hex: string) {
+export function normalizeToHexPubkey(hex: string, require?: boolean): string | null;
+export function normalizeToHexPubkey(hex: string, require: true): string;
+export function normalizeToHexPubkey(hex: string, require = false): string | null {
   if (isHexKey(hex)) return hex;
   try {
     const decode = nip19.decode(hex);
     return getPubkeyFromDecodeResult(decode) ?? null;
   } catch (error) {
-    return null;
+    if (require) throw error;
+    else return null;
   }
 }

src/index.ts

@@ -9,7 +9,7 @@ import duration from "dayjs/plugin/duration.js";
 import localizedFormat from "dayjs/plugin/localizedFormat.js";
 
 import App from "./app/index.js";
-import { PUBLIC_ADDRESS } from "./env.js";
+import { PUBLIC_ADDRESS, IS_MCP } from "./env.js";
 import { addListener, logger } from "./logger.js";
 import { pathExists } from "./helpers/fs.js";
 
@@ -67,12 +67,21 @@ process.on("unhandledRejection", (reason, promise) => {
 // start the app
 await app.start();
 
+// Setup MCP interface on stdio
+if (IS_MCP) {
+  const { StdioServerTransport } = await import("@modelcontextprotocol/sdk/server/stdio.js");
+  const { default: server } = await import("./services/mcp/index.js");
+
+  // connect MCP server to stdio
+  const transport = new StdioServerTransport();
+  await server.connect(transport);
+}
+
 // shutdown process
 async function shutdown() {
   logger("shutting down");
 
   await app.stop();
-
   process.exit(0);
 }
 process.on("SIGINT", shutdown);
@@ -80,10 +89,10 @@ process.on("SIGTERM", shutdown);
 
 // catch unhandled errors
 process.on("uncaughtException", (error) => {
-  console.error("Uncaught Exception:", error);
+  if (!IS_MCP) console.error("Uncaught Exception:", error);
 });
 
 // 2. Catch unhandled promise rejections
 process.on("unhandledRejection", (reason, promise) => {
-  console.error("Unhandled Promise Rejection:", reason);
+  if (!IS_MCP) console.error("Unhandled Promise Rejection:", reason);
 });

src/logger.ts

@@ -1,4 +1,5 @@
 import debug, { Debugger } from "debug";
+import { IS_MCP } from "./env.js";
 
 if (!process.env.DEBUG) debug.enable("bakery,bakery:*");
 
@@ -17,7 +18,9 @@ debug.log = function (this: Debugger, ...args: any[]) {
   for (const listener of listeners) {
     listener(this, ...args);
   }
-  console.log.apply(this, args);
+
+  // only log to console if not running in MCP mode
+  if (!IS_MCP) console.log.apply(this, args);
 };
 
 export const logger = debug("bakery");

src/services/event-cache.ts

@@ -1,7 +1,7 @@
 import { SQLiteEventStore } from "../sqlite/event-store.js";
 import database from "./database.js";
 
-const sqliteEventStore = new SQLiteEventStore(database.db);
-await sqliteEventStore.setup();
+const eventCache = new SQLiteEventStore(database.db);
+await eventCache.setup();
 
-export default sqliteEventStore;
+export default eventCache;

src/services/loaders.ts

@@ -5,11 +5,11 @@ import { ReplaceableLoader, RequestLoader } from "applesauce-loaders/loaders";
 
 import { COMMON_CONTACT_RELAYS } from "../env.js";
 import { rxNostr } from "./rx-nostr.js";
-import sqliteEventStore from "./event-cache.js";
+import eventCache from "./event-cache.js";
 import { eventStore, queryStore } from "./stores.js";
 
 function cacheRequest(filters: Filter[]) {
-  const events = sqliteEventStore.getEventsForFilters(filters);
+  const events = eventCache.getEventsForFilters(filters);
   return from(events).pipe(tap(markFromCache));
 }
 
@@ -20,7 +20,7 @@ replaceableLoader.subscribe((packet) => {
   const event = eventStore.add(packet.event, packet.from);
 
   // save it to the cache if its new
-  if (!isFromCache(event)) sqliteEventStore.addEvent(event);
+  if (!isFromCache(event)) eventCache.addEvent(event);
 });
 
 export const requestLoader = new RequestLoader(queryStore);

src/services/mcp/index.ts

@@ -0,0 +1,5 @@
+import "./resources.js";
+import "./tools.js";
+
+import server from "./server.js";
+export default server;

src/services/mcp/resources.ts

@@ -0,0 +1,35 @@
+import { ResourceTemplate } from "@modelcontextprotocol/sdk/server/mcp.js";
+
+import server from "./server.js";
+import config from "../config.js";
+import { normalizeToHexPubkey } from "../../helpers/nip19.js";
+import { requestLoader } from "../loaders.js";
+
+server.resource("owner pubkey", "pubkey://owner", async (uri) => ({
+  contents: [
+    {
+      uri: uri.href,
+      text: config.data.owner ?? "undefined",
+    },
+  ],
+}));
+
+server.resource(
+  "user profile",
+  new ResourceTemplate("users://{pubkey}/profile", { list: undefined }),
+  async (uri, { pubkey }) => {
+    if (typeof pubkey !== "string") throw new Error("Pubkey must be a string");
+
+    pubkey = normalizeToHexPubkey(pubkey, true);
+    const profile = await requestLoader.profile({ pubkey });
+
+    return {
+      contents: [
+        {
+          uri: uri.href,
+          text: JSON.stringify(profile, null, 2),
+        },
+      ],
+    };
+  },
+);

src/services/mcp/server.ts

@@ -0,0 +1,8 @@
+import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+
+const server = new McpServer({
+  name: "Bakery",
+  version: "1.0.0",
+});
+
+export default server;

src/services/mcp/tools.ts

@@ -0,0 +1,27 @@
+import z from "zod";
+import { kinds } from "nostr-tools";
+
+import server from "./server.js";
+import eventCache from "../event-cache.js";
+
+server.tool(
+  "Search events",
+  "Search events by kind and query",
+  {
+    query: z.string(),
+    kind: z.number().optional().default(kinds.ShortTextNote),
+    limit: z.number().optional().default(50),
+  },
+  async ({ query, kind, limit }) => {
+    const events = eventCache.getEventsForFilters([{ kinds: [kind], search: query, limit }]);
+
+    return {
+      content: events.map((event) => {
+        return {
+          type: "text",
+          text: JSON.stringify(event),
+        };
+      }),
+    };
+  },
+);