Symptom
After the first agent.run(), the httpx.AsyncClient passed to MCPServerStreamableHTTP is closed, and the next run fails with RuntimeError: Cannot reopen a client instance, once it has been closed.
Evidence what you'll see
- http_client.is_closed is True after the first run
- Only when a custom http_client is passed to the MCP server
- Reported on version 0.6.2
Cause
The custom client was handed straight to the MCP transport, which closed it when the session ended.
Fix steps
0 of 1 done
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Verify the fix worked
- Run the agent twice with the same http_client and confirm http_client.is_closed is still False after the first run.
Sources and credit
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