feat: add SSE mode support for MCP server

CHANGELOG.md

@@ -0,0 +1,2 @@
+- Added 'firebase_deploy' and 'firebase_deploy_status' MCP tools.
+- Added SSE mode support to `firebase mcp`. To use it, run `firebase mcp --mode=sse --port=3000`, and connect your client on `http://localhost:3000`.

package.json

@@ -185,6 +185,7 @@
     "@angular-devkit/architect": "^0.1402.2",
     "@angular-devkit/core": "^14.2.2",
     "@google/events": "^5.1.1",
+    "@modelcontextprotocol/ext-apps": "^1.3.2",
     "@types/archiver": "^6.0.0",
     "@types/async-lock": "^1.4.2",
     "@types/body-parser": "^1.17.0",

src/bin/mcp.ts

@@ -49,6 +49,8 @@ Options:
                             If specified, auto-detection is disabled for other features.
   --tools <tools>           Comma-separated list of specific tools to enable. Disables
                             auto-detection entirely.
+  --mode <mode>             Server mode: stdio, sse (defaults to stdio).
+  --port <port>             The port to listen on when running in SSE mode (defaults to 3000).
   -h, --help                Show this help message.
 `;
 
@@ -58,6 +60,8 @@ export async function mcp(): Promise<void> {
       only: { type: "string", default: "" },
       tools: { type: "string", default: "" },
       dir: { type: "string" },
+      mode: { type: "string", default: "stdio" },
+      port: { type: "string", default: "3000" },
       "generate-tool-list": { type: "boolean", default: false },
       "generate-prompt-list": { type: "boolean", default: false },
       "generate-resource-list": { type: "boolean", default: false },
@@ -85,6 +89,11 @@ export async function mcp(): Promise<void> {
   }
   if (earlyExit) return;
 
+  if (values.mode !== "stdio" && values.mode !== "sse") {
+    console.error("Error: --mode must be either 'stdio' or 'sse'");
+    process.exit(1);
+  }
+
   setFirebaseMcp(true);
   // Write debug logs to ~/.cache/firebase to avoid polluting the user's project directory.
   const mcpLogDir = join(homedir(), ".cache", "firebase");
@@ -103,6 +112,9 @@ export async function mcp(): Promise<void> {
     enabledTools,
     projectRoot: values.dir ? resolve(values.dir) : undefined,
   });
-  await server.start();
+  await server.start({
+    useSSE: values.mode === "sse",
+    port: values.port ? parseInt(values.port, 10) : undefined,
+  });
   if (process.stdin.isTTY) process.stderr.write(STARTUP_MESSAGE);
 }

src/experiments.ts

@@ -184,6 +184,11 @@ export const ALL_EXPERIMENTS = experiments({
     default: false,
     public: true,
   },
+  mcpapps: {
+    shortDescription: "Enables MCP Apps features",
+    fullDescription: "Enables MCP Apps features, including returning UI resource URIs.",
+    public: true,
+  },
   fdcift: {
     shortDescription: "Enable instrumentless trial for SQL Connect",
     default: true,