start mcp server in memory

entry.build.ts

@@ -1,39 +0,0 @@
-#!/usr/bin/env node
-
-/**
- * Build entry point - wraps entry.ts to avoid top-level await in CJS output
- */
-
-import * as core from "@actions/core";
-import { type } from "arktype";
-import { Inputs, main } from "./main.ts";
-import packageJson from "./package.json" with { type: "json" };
-import { log } from "./utils/cli.ts";
-
-async function run(): Promise<void> {
-  try {
-    log.info(`🐸 Running pullfrog/action@${packageJson.version}...`);
-
-    const inputsJson = process.env.INPUTS_JSON;
-    if (!inputsJson) {
-      throw new Error("INPUTS_JSON environment variable not found");
-    }
-
-    const parsed = type("string.json.parse").assert(inputsJson);
-    const inputs = Inputs.assert(parsed);
-
-    const result = await main(inputs);
-
-    if (!result.success) {
-      throw new Error(result.error || "Agent execution failed");
-    }
-  } catch (error) {
-    const errorMessage = error instanceof Error ? error.message : "Unknown error occurred";
-    core.setFailed(`Action failed: ${errorMessage}`);
-  }
-}
-
-// Wrap in IIFE to avoid top-level await in CJS
-(async () => {
-  await run();
-})();

entry.ts

@@ -7,9 +7,13 @@
 import * as core from "@actions/core";
 import { type } from "arktype";
 import { Inputs, main } from "./main.ts";
+import { createMcpServer } from "./mcp/server.ts";
 import packageJson from "./package.json" with { type: "json" };
 import { log } from "./utils/cli.ts";
 
+// Export createMcpServer so it can be called from the spawned MCP process
+export { createMcpServer };
+
 async function run(): Promise<void> {
   try {
     log.info(`🐸 Running pullfrog/action@${packageJson.version}...`);
@@ -33,4 +37,11 @@ async function run(): Promise<void> {
   }
 }
 
-await run();
+// Only run main action if INPUTS_JSON is set (running as GitHub Action)
+// When SDK spawns MCP server, it calls createMcpServer() directly
+if (process.env.INPUTS_JSON) {
+  // Wrap in IIFE to avoid top-level await in CJS
+  (async () => {
+    await run();
+  })();
+}

esbuild.config.js

@@ -3,7 +3,7 @@ import { build } from "esbuild";
 // Build the GitHub Action bundle only
 // For npm package builds, use zshy (pnpm build:npm)
 await build({
-  entryPoints: ["./entry.build.ts"],
+  entryPoints: ["./entry.ts"],
   bundle: true,
   outfile: "./entry.cjs",
   format: "cjs",
@@ -11,9 +11,12 @@ await build({
   target: "node20",
   minify: true,
   sourcemap: false,
-  // @actions/core is provided by GitHub Actions runtime, but we still need it bundled
+  // Mark optional peer dependencies as external to avoid bundling errors
-  // for local testing. However, we can mark it to reduce duplication if needed.
+  external: [
-  external: [],
+    "@valibot/to-json-schema",
+    "effect",
+    "sury",
+  ],
   // Enable tree-shaking to remove unused code
   treeShaking: true,
   // Drop console statements in production (but keep for debugging)

mcp/config.ts

@@ -3,11 +3,8 @@
  */
 
 import type { McpServerConfig } from "@anthropic-ai/claude-agent-sdk";
-import { fromHere } from "@ark/fs";
 import { parseRepoContext } from "../utils/github.ts";
 
-const actionPath = fromHere("..");
-
 export const ghPullfrogMcpName = "gh-pullfrog";
 
 export type McpName = typeof ghPullfrogMcpName;
@@ -18,10 +15,15 @@ export function createMcpConfigs(githubInstallationToken: string): McpConfigs {
   const repoContext = parseRepoContext();
   const githubRepository = `${repoContext.owner}/${repoContext.name}`;
 
+  // Get absolute path to entry.cjs - use GITHUB_ACTION_PATH if available, otherwise current directory
+  const entryPath = process.env.GITHUB_ACTION_PATH
+    ? `${process.env.GITHUB_ACTION_PATH}/entry.cjs`
+    : `${process.cwd()}/entry.cjs`;
+
   return {
     [ghPullfrogMcpName]: {
       command: "node",
-      args: [`${actionPath}/mcp/server.ts`],
+      args: ["-e", `require('${entryPath.replace(/'/g, "\\'")}').createMcpServer()`],
       env: {
         GITHUB_INSTALLATION_TOKEN: githubInstallationToken,
         GITHUB_REPOSITORY: githubRepository,

mcp/server.ts

@@ -8,18 +8,20 @@ import { PullRequestInfoTool } from "./prInfo.ts";
 import { ReviewTool } from "./review.ts";
 import { addTools } from "./shared.ts";
 
-const server = new FastMCP({
+export function createMcpServer(): void {
-  name: "gh-pullfrog",
+  const server = new FastMCP({
-  version: "0.0.1",
+    name: "gh-pullfrog",
-});
+    version: "0.0.1",
+  });
 
-addTools(server, [
+  addTools(server, [
-  CreateCommentTool,
+    CreateCommentTool,
-  EditCommentTool,
+    EditCommentTool,
-  IssueTool,
+    IssueTool,
-  PullRequestTool,
+    PullRequestTool,
-  ReviewTool,
+    ReviewTool,
-  PullRequestInfoTool,
+    PullRequestInfoTool,
-]);
+  ]);
 
-server.start();
+  server.start();
+}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@pullfrog/action",
-  "version": "0.0.74",
+  "version": "0.0.75",
   "type": "module",
   "files": [
     "index.js",