[Bug] agents-cli playground fails on Windows due to wildcard expansion of --allow_origins "*"

[Abdullah-k0de]

What happened?

Running agents-cli playground on Windows crashes with Error: Got unexpected extra arguments showing files from the current working directory.

Steps to Reproduce

1. Create an agent project on Windows.
2. Open a terminal inside the project root folder.
3. Run agents-cli install
4. Run agents-cli playground

What did you expect to happen?

The local playground server starts successfully and hosts the web UI at http://127.0.0.1:8080/dev-ui/

Client information

CLI version: 0.5.0
CLI install path: C:\Users\abdul\AppData\Roaming\uv\tools\google-agents-cli\Lib\site-packages\google\agents\cli
OS info: Windows-11-10.0.26200-SP0
Installed skills: none

Project root: C:\Users\abdul\OneDrive\Desktop\Comp Lang NEW\Antigravity - agy-cli-projects\weather-assistant
Project name: weather-assistant
Deployment target: none
Agent directory: app
Region: us-east1

Command Output / Logs

agents-cli playground
Starting your agent playground...
Running command: uv run adk web . --host 127.0.0.1 --port 8080 --allow_origins '*' --reload_agents
Will be available at: http://127.0.0.1:8080/dev-ui/?app=app
Usage: adk web [OPTIONS] [AGENTS_DIR]
Try 'adk web --help' for help.

Error: Got unexpected extra arguments (app Dockerfile GEMINI.md pyproject.toml README.md tests uv.lock)
agents-cli v0.5.0
Error: Failed to start playground (exit code 2)

Anything else we need to know?

Cause:

When Python launches the command via uv run, the adk.exe launcher wrapper (which is compiled with MSVC's setargv.obj) automatically expands the * wildcard in --allow_origins "*" into all filenames in the current directory before passing it to Python. Click then interprets these filenames as unexpected positional arguments.

Proposed Fix:

In google/agents/cli/dev/cmd_playground.py, escape/quote the asterisk argument on Windows to prevent the launcher's C runtime from expanding it:

     browser_host = "127.0.0.1" if host == "0.0.0.0" else host
     url = f"http://{browser_host}:{port}/dev-ui/?app={cfg.agent_directory}"
 
+    import sys
+    allow_origins = '"*"' if sys.platform == "win32" else "*"
     args = [
         "uv",
         "run",
@@ -66,7 +66,7 @@
         "--port",
         str(port),
         "--allow_origins",
-        "*",
+        allow_origins,
     ]
     if reload_agents:
         args.append("--reload_agents")


---

*Contribution & Recognition:*
*   I have signed the Google Individual CLA (under the name Abdullah).
*   Since this fix resolves a blocker for Windows users, I would appreciate being credited for this contribution when the fix is applied.
*   Once merged, I would also love to be nominated for the Google Open Source Peer Bonus program.

[sushicw]

Thank you for the report!

This actually appears to be an ADK cli bug, the same behavior occurs if you do uv run adk web . --host 127.0.0.1 --port 8080 --allow_origins '*' --reload_agents directly and don't involve agents-cli at all. A quoted * should not be getting expanded.

In the meantime, we're adding a workaround in agents-cli to unblock Windows usage.

[Abdullah-k0de]

Thank you for the quick response and for self-assigning this!

Yes, it is indeed an issue with how the compiled adk.exe launcher wrapper handles argument parsing/expansion on Windows. I'm glad the workaround will be added to agents-cli to unblock Windows users in the meantime.

Also, I have just filed another issue regarding two other Windows-specific blockers in the agents-cli run local server lifecycle (a startup crash 0xc0000142 and a shutdown crash WNOHANG in _local_server.py), along with the proposed fixes.

Since I've signed the CLA, I'm excited to contribute and help stabilize the Windows experience. I appreciate the support and would love to collaborate on future fixes/nominations!