Is Tool Search always sent in requests?

[arthurfujii-cit]

I'm having a problem that all requests are being sent with the tool_search parameter, but the Sonnet 5 provider that I'm using do not accept that, returning a 400 http error. I've tryed the workaround approach from here(#2660), changing OPENAI with ANTHROPIC in var. I've also changed the ENABLE_TOOL_SEARCH to false, but no success.
Someone having this problem too? Am I missing something?

[CasperKristiansson]

I think you are disabling the client-side setting, while the request is being modified by Headroom’s server-side setting. They are separate:

• ENABLE_TOOL_SEARCH controls Claude Code’s own deferred tool loading.
• HEADROOM_TOOL_SEARCH controls Headroom’s proxy-side tool-search injection.

The default coding profile sets HEADROOM_TOOL_SEARCH=1, so changing only ENABLE_TOOL_SEARCH will not stop the proxy from adding the tool-search fields.

Set this in the environment of the proxy process before starting it:

export HEADROOM_TOOL_SEARCH=0
headroom proxy

Or, if you launch through the wrapper:

HEADROOM_TOOL_SEARCH=0 headroom wrap claude

Make sure to fully stop and restart any already-running or persistent Headroom proxy. Changing the variable in the client shell will not change the environment of a proxy process that is already running.

The workaround from #2660 is specific to the OpenAI Responses path: HEADROOM_OPENAI_TOOL_SEARCH_MODELS is only read by the OpenAI helper. Renaming that variable to use ANTHROPIC will not affect the Anthropic handler. That handler checks HEADROOM_TOOL_SEARCH directly.

An explicit value of 0 should win over the default profile because Headroom applies profile values with setdefault(). You can leave ENABLE_TOOL_SEARCH=false as well if your client/provider does not support its own tool-search flow, but it is HEADROOM_TOOL_SEARCH=0 on the proxy that should stop this particular injection.

[arthurfujii-cit]

Thank you! That is it! HEADROOM_TOOL_SEARCH is something different than ENABLE_TOOL_SEARCH!
The wrap, even if disabling the tool search is insisting to send the parameter, but if I set the HEADROOM_TOOL_SEARCH=0 to the headroom proxy, then I just set the claude's urls, it works as desired!
thank you again!