Panda integration temp/not finished.

benchmarks/page-token-benchmark/config/conditions.yaml

@@ -1,6 +1,7 @@
 # Each condition defines how to fetch a page snapshot.
 # tool_mode: cli   → runs `<cli_bin> <nav_cmd> <url> [--raw]` as a subprocess
 # tool_mode: bridge → calls navigate_page via the bridge HTTP API
+# tool_mode: lightpanda → runs `lightpanda fetch --dump <dump> --log-level error <url>` as a subprocess
 
 - id: opera-compact
   description: opera-browser-cli compact snapshot, full page (--full)
@@ -37,3 +38,49 @@
     - "chrome-devtools-axi stop"
     - "chrome-devtools-axi start"
   stop: "chrome-devtools-axi stop"
+
+- id: lightpanda-fetch-markdown
+  description: lightpanda fetch --dump markdown (one-shot, no CDP/bridge)
+  tool_mode: lightpanda
+  cli_bin: lightpanda
+  dump: markdown
+
+- id: lightpanda-fetch-html
+  description: lightpanda fetch --dump html (one-shot, raw DOM)
+  tool_mode: lightpanda
+  cli_bin: lightpanda
+  dump: html
+
+- id: lightpanda-fetch-semantic-tree
+  description: lightpanda fetch --dump semantic_tree_text (pruned plain-text tree)
+  tool_mode: lightpanda
+  cli_bin: lightpanda
+  dump: semantic_tree_text
+
+- id: panda-compact
+  description: opera-browser-cli with panda backend, compact snapshot, full page (--full)
+  tool_mode: cli
+  cli_bin: /Users/opera_user/work/opera-browser-cli/dist/bin/opera-browser-cli.js
+  nav_cmd: open
+  raw: false
+  full: true
+  env:
+    OPERA_CLI_BROWSER_BACKEND: panda
+    OPERA_CLI_LIGHTPANDA_BIN: /Users/opera_user/work/browser/zig-out/bin/lightpanda
+  start:
+    - /Users/opera_user/work/opera-browser-cli/dist/bin/opera-browser-cli.js stop
+  stop: /Users/opera_user/work/opera-browser-cli/dist/bin/opera-browser-cli.js stop
+
+- id: panda-raw
+  description: opera-browser-cli with panda backend, uncompressed MCP output (--raw --full)
+  tool_mode: cli
+  cli_bin: /Users/opera_user/work/opera-browser-cli/dist/bin/opera-browser-cli.js
+  nav_cmd: open
+  raw: true
+  full: true
+  env:
+    OPERA_CLI_BROWSER_BACKEND: panda
+    OPERA_CLI_LIGHTPANDA_BIN: /Users/opera_user/work/browser/zig-out/bin/lightpanda
+  start:
+    - /Users/opera_user/work/opera-browser-cli/dist/bin/opera-browser-cli.js stop
+  stop: /Users/opera_user/work/opera-browser-cli/dist/bin/opera-browser-cli.js stop

benchmarks/page-token-benchmark/src/cli_runner.py

@@ -129,6 +129,46 @@ def run_bridge(url: str, bridge_url: str, timeout: int) -> RunResult:
         return RunResult(stdout="", stderr="", returncode=-1, wall_seconds=wall, error=str(exc))
 
 
+def run_lightpanda_fetch(
+    url: str,
+    cli_bin: str,
+    dump: str,
+    timeout: int,
+) -> RunResult:
+    """One-shot Lightpanda fetch: `lightpanda fetch --dump <fmt> --log-level error <url>`.
+
+    Dump renders to stdout; logs go to stderr; no server/bridge/CDP involved.
+    `dump` is one of `markdown | html | semantic_tree | semantic_tree_text`.
+
+    Note: Lightpanda `fetch` exits 0 even when navigation fails (it prints
+    ``# Navigation failed`` to stdout), so failure is detected separately.
+    """
+    cmd = [cli_bin, "fetch", "--dump", dump, "--log-level", "error", url]
+    start = time.monotonic()
+    try:
+        proc = subprocess.run(cmd, capture_output=True, text=True, timeout=timeout)
+        wall = time.monotonic() - start
+        error = _detect_error(proc.stdout, proc.returncode)
+        if error is None:
+            stripped = proc.stdout.lstrip()
+            if stripped.startswith("# Navigation failed") or "CouldntConnect" in stripped:
+                error = stripped.splitlines()[0] if stripped.splitlines() else "navigation failed"
+        return RunResult(
+            stdout=proc.stdout,
+            stderr=proc.stderr,
+            returncode=proc.returncode,
+            wall_seconds=wall,
+            error=error,
+        )
+    except subprocess.TimeoutExpired:
+        wall = time.monotonic() - start
+        return RunResult(stdout="", stderr="", returncode=-1, wall_seconds=wall,
+                         error=f"timeout after {timeout}s: {shlex.join(cmd)}")
+    except Exception as exc:
+        wall = time.monotonic() - start
+        return RunResult(stdout="", stderr="", returncode=-1, wall_seconds=wall, error=str(exc))
+
+
 def run_condition(url: str, condition: dict, timeout: int = 60) -> RunResult:
     """Dispatch to the right runner based on condition tool_mode."""
     mode = condition["tool_mode"]
@@ -145,4 +185,12 @@ def run_condition(url: str, condition: dict, timeout: int = 60) -> RunResult:
         )
     if mode == "bridge":
         return run_bridge(url, bridge_url=condition.get("bridge_url", "http://localhost:9224"), timeout=timeout)
+    if mode == "lightpanda":
+        return run_lightpanda_fetch(
+            url,
+            cli_bin=condition.get("cli_bin", "lightpanda"),
+            dump=condition.get("dump", "markdown"),
+            timeout=timeout,
+        )
+
     raise ValueError(f"Unknown tool_mode: {mode}")

bin/panda-mcp-adapter.ts

@@ -0,0 +1,8 @@
+#!/usr/bin/env node
+import { main } from "../src/panda-mcp-adapter.js";
+
+main(process.argv.slice(2)).catch((error: unknown) => {
+  const message = error instanceof Error ? error.message : String(error);
+  process.stderr.write(`[panda-mcp-adapter] Fatal: ${message}\n`);
+  process.exit(1);
+});

package.json

@@ -18,7 +18,8 @@
     "mcp"
   ],
   "bin": {
-    "opera-browser-cli": "dist/bin/opera-browser-cli.js"
+    "opera-browser-cli": "dist/bin/opera-browser-cli.js",
+    "panda-mcp-adapter": "dist/bin/panda-mcp-adapter.js"
   },
   "files": [
     "dist",

src/bridge.ts

@@ -36,6 +36,7 @@ import {
   type BridgeHealth,
 } from "./identity.js";
 import { getPackageVersion } from "./version.js";
+import { detectLightpanda } from "./detect.js";
 
 const DEFAULT_PORT = Number.parseInt(
   process.env.OPERA_CLI_PORT ?? "9225",
@@ -666,6 +667,7 @@ export function shouldRunHeaded(): boolean {
 }
 
 export function buildTransportArgs(): string[] {
+  if (isPandaBackend()) return buildPandaTransportArgs();
   const args: string[] = [];
 
   const browserUrl = process.env.OPERA_CLI_BROWSER_URL;
@@ -713,6 +715,44 @@ export function buildTransportArgs(): string[] {
   return args;
 }
 
+/** True when the Lightpanda ("panda") backend is selected instead of Chrome/Opera. */
+export function isPandaBackend(): boolean {
+  return process.env.OPERA_CLI_BROWSER_BACKEND === "panda";
+}
+
+/**
+ * Args for the panda adapter shim. Unlike Chrome, there are no browser-launch
+ * flags to forward — the shim resolves the lightpanda binary itself. We hand it
+ * the resolved path so `doctor` and the shim agree on the same binary.
+ */
+function buildPandaTransportArgs(): string[] {
+  const lightpanda = detectLightpanda();
+  return lightpanda ? [`--lightpanda-bin=${lightpanda}`] : [];
+}
+
+/** Resolve the adapter shim script path (OPERA_CLI_MCP_BIN override, else bundled). */
+function resolvePandaAdapterScript(): string {
+  if (process.env.OPERA_CLI_MCP_BIN) return process.env.OPERA_CLI_MCP_BIN;
+  const built = resolve(import.meta.dirname, "../bin/panda-mcp-adapter.js");
+  const source = built.replace(/\.js$/, ".ts");
+  return existsSync(source) ? source : built;
+}
+
+/** Decide how to launch the panda adapter shim, mirroring resolveBridgeLauncher. */
+function resolvePandaAdapterLauncher(): BridgeLauncher {
+  const built = resolve(import.meta.dirname, "../bin/panda-mcp-adapter.js");
+  const source = built.replace(/\.js$/, ".ts");
+  const preferSource =
+    process.env.OPERA_CLI_DEV === "1" || !existsSync(built);
+  if (preferSource && existsSync(source)) {
+    const tsx = resolveTsxCli();
+    if (tsx === null) return { ok: false, reason: "tsx-not-installed" };
+    return { ok: true, command: process.execPath, args: [tsx, source] };
+  }
+  if (!existsSync(built)) return { ok: false, reason: "panda-adapter-not-built" };
+  return { ok: true, command: process.execPath, args: [built] };
+}
+
 export interface McpBinStatus {
   bin: string;
   found: boolean;
@@ -742,6 +782,14 @@ function existsOnPath(command: string): boolean {
  * bridge start.
  */
 export function resolveMcpBinStatus(): McpBinStatus {
+  if (isPandaBackend()) {
+    const bin = resolveOperaMcpBin();
+    return {
+      bin,
+      found: existsSync(bin) || existsOnPath(bin),
+      source: process.env.OPERA_CLI_MCP_BIN ? "env" : "dependency",
+    };
+  }
   const bin = resolveOperaMcpBin();
   if (process.env.OPERA_CLI_MCP_BIN) {
     return { bin, found: existsSync(bin) || existsOnPath(bin), source: "env" };
@@ -753,6 +801,7 @@ export function resolveMcpBinStatus(): McpBinStatus {
 }
 
 function resolveOperaMcpBin(): string {
+  if (isPandaBackend()) return resolvePandaAdapterScript();
   if (process.env.OPERA_CLI_MCP_BIN) return process.env.OPERA_CLI_MCP_BIN;
   try {
     const require = createRequire(import.meta.url);
@@ -776,6 +825,16 @@ function resolveOperaMcpBin(): string {
 }
 
 function createTransport(): StdioClientTransport {
+  if (isPandaBackend()) {
+    const launcher = resolvePandaAdapterLauncher();
+    if (!launcher.ok) {
+      throw new Error(`Cannot launch the panda adapter: ${launcher.reason}`);
+    }
+    return new StdioClientTransport({
+      command: launcher.command,
+      args: [...launcher.args, ...buildPandaTransportArgs()],
+    });
+  }
   const bin = resolveOperaMcpBin();
   const args = buildTransportArgs();
   if (bin.endsWith(".js")) {

src/browser-target.ts

@@ -140,6 +140,7 @@ export async function launchAttachableBrowser(
   executablePath: string | undefined,
   userDataDir: string,
   extraArgs: string[] = [],
+  headless = false,
   timeoutMs = 30_000,
 ): Promise<LaunchResult> {
   if (!executablePath || !existsSync(executablePath)) {
@@ -166,6 +167,10 @@ export async function launchAttachableBrowser(
     ...extraArgs,
   ];
 
+  if (headless) {
+    args.push("--headless");
+  }
+
   let child;
   try {
     child = spawn(executablePath, args, { stdio: "ignore", detached: true });