feat: connect registries to Pi, OMP and MCP

README.md

@@ -103,6 +103,26 @@ The tool supports these operations through one input schema:
 // { operation: 'bulk-packages', purls: ['pkg:npm/lodash', 'pkg:cargo/serde'], concurrency?: number }
 ```
 
+### MCP
+
+The package ships an MCP server with six read-only tools for metadata, versions, dependencies, maintainers, bulk lookups, and ecosystem discovery:
+
+```bash
+claude mcp add registries --scope user -- npx @agntn/registries mcp
+```
+
+Hosts with their own transport can import `createMcpServer` from `@agntn/registries/mcp`.
+
+### Pi and OMP extensions
+
+Install the published package in OMP:
+
+```bash
+omp install @agntn/registries
+```
+
+From a source checkout, use `omp install .`. The package manifests point OMP and Pi at their matching extension entrypoints, and both expose the same six read-only tools as MCP.
+
 ## Registries
 
 | Ecosystem  | PURL type          | Registry                         |
@@ -231,6 +251,7 @@ registries <command> [options]
 | `registries versions <purl>`    | List all published versions                            |
 | `registries deps <purl>`        | Dependencies for a specific version                    |
 | `registries maintainers <purl>` | Package maintainers / authors                          |
+| `registries mcp`                | Start the MCP server over stdio                        |
 | `registries cache status`       | Show cache stats (entries, freshness)                  |
 | `registries cache path`         | Print cache directory path                             |
 | `registries cache clear`        | Remove all cached data                                 |

build.config.ts

@@ -1,4 +1,24 @@
 import { defineBuildConfig } from "obuild/config";
+import type { BuildConfig } from "obuild";
+
+const bundleTypeboxHook: NonNullable<BuildConfig["hooks"]> = {
+  rolldownConfig(config) {
+    const originalExternal = config.external;
+    const isTypebox = (id: string) => /^typebox(?:\/|$)/.test(id);
+
+    if (typeof originalExternal === "function") {
+      config.external = async (id, importer, isResolved) =>
+        isTypebox(id) ? false : originalExternal(id, importer, isResolved);
+      return;
+    }
+
+    if (Array.isArray(originalExternal)) {
+      config.external = originalExternal.filter(
+        (item) => !(typeof item === "string" && isTypebox(item)),
+      );
+    }
+  },
+};
 
 export default defineBuildConfig({
   entries: [
@@ -7,27 +27,14 @@ export default defineBuildConfig({
       input: [
         "./src/index.ts",
         "./src/ai.ts",
-        "./src/types.ts",
-        "./src/core/index.ts",
         "./src/registries/index.ts",
-        "./src/cli.ts",
-        "./src/commands/shared.ts",
-        "./src/commands/info.ts",
-        "./src/commands/versions.ts",
-        "./src/commands/deps.ts",
-        "./src/commands/maintainers.ts",
-        "./src/commands/cache.ts",
-
         "./src/cache/index.ts",
-
-        "./src/cache/paths.ts",
-
-        "./src/cache/lockfile.ts",
-
-        "./src/cache/storage.ts",
-
-        "./src/cache/cached-registry.ts",
+        "./src/cli.ts",
+        "./src/mcp.ts",
+        "./src/tool-operations.ts",
       ],
+      dts: true,
     },
   ],
+  hooks: bundleTypeboxHook,
 });

oxlint.config.ts

@@ -12,7 +12,7 @@ export default defineConfig({
           { from: "file", name: "ToolResult" },
           {
             from: "package",
-            name: "ExtensionAPI",
+            name: ["ExtensionAPI", "ToolDefinition"],
             package: "@earendil-works/pi-coding-agent",
           },
           {

package.json

@@ -4,10 +4,12 @@
   "description": "Universal package registry client. Query npm, PyPI, crates.io, RubyGems, Packagist and more with a single PURL-native API.",
   "keywords": [
     "crates",
+    "mcp",
     "metadata",
     "npm",
     "package-registry",
     "packagist",
+    "pi-extension",
     "purl",
     "pypi",
     "rubygems",
@@ -25,7 +27,9 @@
     "registries": "./dist/cli.mjs"
   },
   "files": [
-    "dist"
+    "dist",
+    "packages/pi/extensions",
+    "packages/omp/extensions"
   ],
   "type": "module",
   "sideEffects": [
@@ -46,6 +50,10 @@
       "types": "./dist/ai.d.mts",
       "import": "./dist/ai.mjs"
     },
+    "./mcp": {
+      "types": "./dist/mcp.d.mts",
+      "import": "./dist/mcp.mjs"
+    },
     "./registries": {
       "types": "./dist/registries/index.d.mts",
       "import": "./dist/registries/index.mjs"
@@ -61,9 +69,10 @@
   "scripts": {
     "build": "obuild",
     "dev:prepare": "obuild --stub",
-    "fmt": "oxlint . --fix && oxfmt .",
-    "lint": "oxlint . && oxfmt --check .",
-    "typecheck": "tsc --noEmit && tsc -p test/tsconfig.json --noEmit",
+    "fmt": "pnpm lint:fix",
+    "lint": "pnpm build && oxlint . && oxfmt --check .",
+    "lint:fix": "oxlint . --fix && oxfmt .",
+    "typecheck": "tsc --noEmit && tsc -p test/tsconfig.json --noEmit && pnpm build && tsc -p tsconfig.extensions.json --noEmit",
     "test": "vitest",
     "test:run": "vitest run",
     "prepack": "pnpm run build",
@@ -72,13 +81,18 @@
     "docs:build": "pnpm --dir docs build"
   },
   "dependencies": {
+    "@modelcontextprotocol/sdk": "^1.30.0",
     "citty": "^0.2.1",
     "consola": "^3.4.2",
     "ofetch": "^1.5.1",
+    "typebox": "^1.3.25",
     "unstorage": "^1.17.4"
   },
   "devDependencies": {
     "@agntn/ox": "^0.1.0",
+    "@earendil-works/pi-coding-agent": "0.84.2",
+    "@oh-my-pi/omptype": "18.0.0",
+    "@oh-my-pi/pi-coding-agent": "18.0.0",
     "@types/node": "^25.3.0",
     "ai": "^6.0.116",
     "changelogen": "^0.6.2",
@@ -91,10 +105,18 @@
     "zod": "^4.3.6"
   },
   "peerDependencies": {
+    "@earendil-works/pi-coding-agent": ">=0.84.2",
+    "@oh-my-pi/pi-coding-agent": ">=18.0.0",
     "ai": "^6.0.116",
     "zod": "^4.3.6"
   },
   "peerDependenciesMeta": {
+    "@earendil-works/pi-coding-agent": {
+      "optional": true
+    },
+    "@oh-my-pi/pi-coding-agent": {
+      "optional": true
+    },
     "ai": {
       "optional": true
     },
@@ -105,5 +127,24 @@
   "engines": {
     "node": ">=22.6.0"
   },
-  "packageManager": "pnpm@11.3.0"
+  "packageManager": "pnpm@11.3.0",
+  "mcpServers": {
+    "registries": {
+      "command": "node",
+      "args": [
+        "dist/cli.mjs",
+        "mcp"
+      ]
+    }
+  },
+  "omp": {
+    "extensions": [
+      "./packages/omp/extensions/registries.ts"
+    ]
+  },
+  "pi": {
+    "extensions": [
+      "./packages/pi/extensions/registries.ts"
+    ]
+  }
 }

packages/AGENTS.md

@@ -0,0 +1,10 @@
+# Agent runtime integrations
+
+This subtree contains distributable Pi and OMP extensions for `@agntn/registries`.
+
+- Extension entrypoints must stay source-first for local development and fall back to built files from `dist/` in packed installations.
+- Pi may choose the source or distribution module dynamically.
+- OMP requires literal imports for both source and distribution paths because its loader rewrites visible imports.
+- Tool execution belongs in `src/tool-operations.ts`; extensions only declare host metadata and delegate.
+- All registry operations are read-only. OMP tools declare `approval: "read"`.
+- Keep tool names, schemas, descriptions, and tests aligned across Pi, OMP, and MCP.

packages/omp/extensions/registries.ts

@@ -0,0 +1,112 @@
+import { existsSync } from "node:fs";
+import { fileURLToPath } from "node:url";
+
+import type { AgentToolResult, ExtensionAPI } from "@oh-my-pi/pi-coding-agent";
+
+import type * as RegistryTools from "../../../dist/tool-operations.d.mts";
+
+const sourceModulePath = fileURLToPath(new URL("../../../src/tool-operations.ts", import.meta.url));
+let toolOperationsPromise: Promise<typeof RegistryTools> | undefined;
+
+function loadToolOperations(): Promise<typeof RegistryTools> {
+  toolOperationsPromise ??= (
+    existsSync(sourceModulePath)
+      ? import("../../../src/tool-operations.ts")
+      : import("../../../dist/tool-operations.mjs")
+  ) as Promise<typeof RegistryTools>;
+  return toolOperationsPromise;
+}
+
+type RegistryToolResult = AgentToolResult<unknown>;
+
+export default function registriesExtension(pi: ExtensionAPI): void {
+  const { Type } = pi.typebox;
+  const PURL = Type.String({
+    minLength: 1,
+    maxLength: 2_048,
+    description: "Package URL, for example pkg:npm/lodash or pkg:pypi/requests@2.32.3",
+  });
+  const PURLParams = Type.Object({ purl: PURL }, { additionalProperties: false });
+  const BulkPackagesParams = Type.Object(
+    {
+      purls: Type.Array(PURL, { minItems: 1, maxItems: 50 }),
+      concurrency: Type.Optional(Type.Integer({ minimum: 1, maximum: 50 })),
+    },
+    { additionalProperties: false },
+  );
+  const EmptyParams = Type.Object({}, { additionalProperties: false });
+
+  pi.setLabel("Registries");
+
+  pi.registerTool({
+    name: "registries_package",
+    label: "Registry Package",
+    description: "Fetch normalized metadata for one package URL",
+    parameters: PURLParams,
+    approval: "read",
+    async execute(_toolCallId, params, signal): Promise<RegistryToolResult> {
+      const { packageOperation } = await loadToolOperations();
+      return packageOperation(params, signal);
+    },
+  });
+
+  pi.registerTool({
+    name: "registries_versions",
+    label: "Registry Versions",
+    description: "List normalized versions for one package URL",
+    parameters: PURLParams,
+    approval: "read",
+    async execute(_toolCallId, params, signal): Promise<RegistryToolResult> {
+      const { versionsOperation } = await loadToolOperations();
+      return versionsOperation(params, signal);
+    },
+  });
+
+  pi.registerTool({
+    name: "registries_dependencies",
+    label: "Registry Dependencies",
+    description: "List dependencies for a versioned package URL",
+    parameters: PURLParams,
+    approval: "read",
+    async execute(_toolCallId, params, signal): Promise<RegistryToolResult> {
+      const { dependenciesOperation } = await loadToolOperations();
+      return dependenciesOperation(params, signal);
+    },
+  });
+
+  pi.registerTool({
+    name: "registries_maintainers",
+    label: "Registry Maintainers",
+    description: "List normalized maintainers for one package URL",
+    parameters: PURLParams,
+    approval: "read",
+    async execute(_toolCallId, params, signal): Promise<RegistryToolResult> {
+      const { maintainersOperation } = await loadToolOperations();
+      return maintainersOperation(params, signal);
+    },
+  });
+
+  pi.registerTool({
+    name: "registries_bulk_packages",
+    label: "Registry Bulk Packages",
+    description: "Fetch normalized metadata for up to 50 package URLs",
+    parameters: BulkPackagesParams,
+    approval: "read",
+    async execute(_toolCallId, params, signal): Promise<RegistryToolResult> {
+      const { bulkPackagesOperation } = await loadToolOperations();
+      return bulkPackagesOperation(params, signal);
+    },
+  });
+
+  pi.registerTool({
+    name: "registries_ecosystems",
+    label: "Registry Ecosystems",
+    description: "List package ecosystems registered by this package",
+    parameters: EmptyParams,
+    approval: "read",
+    async execute(): Promise<RegistryToolResult> {
+      const { ecosystemsOperation } = await loadToolOperations();
+      return ecosystemsOperation();
+    },
+  });
+}