Summary

When using cagent with a LiteLLM proxy (OpenAI-compatible API), a subagent can return a valid tool_calls response, but the host agent reports “no response from subagent” and does not execute the tool call.

Environment

• cagent: v1.19.7
• OS: Linux (WSL2) x86_64
• LLM: gemini-pro via LiteLLM proxy (OpenAI-compatible)

Expected

Host agent receives the subagent response and executes the tool call(s), then continues the conversation with the tool result.

Actual

Host agent reports there is “no response from subagent” even though the subagent response contains a valid tool_calls entry. The requested tool call is not executed.

Minimal reproduction

1. Configure cagent to use LiteLLM as the model provider (OpenAI-compatible API).
2. Run a workflow where the subagent is asked to use tools.
3. The subagent returns a tool call (e.g., company_search with JSON arguments) and finishes with finish_reason: "stop".
4. The host agent logs “no response from subagent” and does not invoke the tool.

Notes

• The subagent response includes a valid tool call object (type: function, name: company_search, arguments: {"datasources": ["confluence", "github", "gdrive"], "query": "LiteLLM usage teams integrations standards"}).
• I can reproduce consistently with LiteLLM as the proxy in front of an OpenAI-compatible endpoint.

Please let me know if you want a sanitized example payload or a minimal agent config.