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I have a small problem. Basically, in my prompt I specify that when a tool is called, its ID must be included. However, when my tool is actually called, the ID is not passed in the arguments field. Instead, a random ID starting with "call_..." is sent in the payload. How can I fix this? Earlier today it was working normally.

String is actually the native Tool Call ID the LLM generates automatically. If it was working earlier and suddenly stopped, the model provider (OpenAI/Groq/etc.) probably pushed an update that's strictly enforcing their standard tool-calling schema.
Basically, the model's internal logic is overriding your prompt instructions.

Instead of fighting the model to put a custom ID in the arguments field, just grab that call_... ID from the payload and use it on your backend to track the request. It’s way more reliable.
If you really need a custom ID, try renaming that field in your tool's JSON schema to something super specific like internal_ref_id so the model doesn't get confused. 👊
If you want me to help you rename that field in your tool schema to see if it sticks?

Hi, could you please provide us with the affected call IDs?