Describe the bug

agentscope.tool.execute_shell_command can deadlock when the child process writes more to stdout/stderr than the OS pipe buffer (often ~64KB). The parent waits for the process to exit with proc.wait() while not reading the pipes; the child blocks on writing once the buffer is full. Neither side progresses.

To Reproduce

1. Code (async):

import asyncio
from agentscope.tool import execute_shell_command

async def main():
    # GitHub releases API returns a large JSON (often >64KB)
    resp = await execute_shell_command(
        command='curl -s -H "Accept: application/vnd.github+json" '
                '"https://api.github.com/repos/agentscope-ai/agentscope/releases"',
        timeout=60,
    )
    print(resp)

asyncio.run(main())

2. Run: python repro.py

3. Observe: The script hangs and never prints. The same curl command runs to completion in a normal terminal.

Expected behavior

The tool should return with <returncode>0</returncode>, <stdout>...</stdout> containing the API response, and no hang.

Error messages

There is no exception or error message; the call simply blocks indefinitely (until timeout, if any).

Environment

• AgentScope Version: 1.0.13
• Python Version: 3.12
• OS: macOS (darwin)

Additional context

Root cause: In _shell.py, the implementation does:

await asyncio.wait_for(proc.wait(), timeout=timeout)
stdout, stderr = await proc.communicate()

Waiting for the process with proc.wait() without reading stdout/stderr allows the pipe buffers to fill. Once they are full, the child blocks on write() and never exits, so proc.wait() never returns → deadlock.