Not able of making tool calls and response format at the same time

TL;DR

If removed one of the arguments it does work. What works: Use this workaround on the Agno model config.

Steps

1. What was reported:

Issue agno-agi/agno#2612 (closed, 21 comments): # Description A simple agent is not able of having tools and response_model at the same time. If removed one of the arguments it does work.

When to use

You are seeing this: What was reported: Issue agno-agi/agno#2612 (closed, 21 comments): # Description A simple agent is not able of having tools and response_model at the same time. Use this skill when you run into "Not able of making tool calls and response format at the same time".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Edge cases

• Caveats: it is less stable than native structured outputs, and later users still reported broader tool-calling and output-schema failures with some providers, so treat it as a workaround rather than a full fix.

In the GitHub issue, the reporter asked: Not able of making tool calls and response format at the same time. The working answer that came out of the thread: Use this workaround on the Agno model config. It forces JSON text output that Agno then parses into your schema:

supportsnativestructuredoutputs=False supportsjsonschemaoutputs=True usejsonmode=False structuredoutputs=True responsemodel=YourSchema

Multiple users confirmed this gets Gemini and OpenRouter models to return valid structured output with Agno. Caveats: it is less stable than native structured outputs, and later users still reported broader tool-calling and output-schema failures with some providers, so treat it as a workaround rather than a full fix. Source: https://github.com/agno-agi/agno/issues/2612