Bug type

Regression (worked before, now fails)

Beta release blocker

No

Summary

After upgrading from 2026.4.14 to 2026.4.15, configured use model github-copilot/gpt-5-mini, worked at first message, failed in later messages, the error is : LLM request failed: provider rejected the request schema or tool payload.

it's also failed with github-copilot/raptor-mini

Steps to reproduce

1. Start Openclaw 2026.4.15
2. configure use model github-copilot/gpt-5-mini
3. send message , example Hi
4. after received response, send another message, example Hi again
5. error occured: LLM request failed: provider rejected the request schema or tool payload.

Expected behavior

In 2026.4.15, it should be OK when send any messages.

Actual behavior

worked at first message, failed in later messages, the error is : LLM request failed: provider rejected the request schema or tool payload.

OpenClaw version

2026.4.15

Operating system

Ubuntu 24.04

Install method

npm global

Model

github-copilot/gpt-5-mini

Provider / routing chain

openclaw->github-copilot->gpt-5-mini

Additional provider/model setup details

No response

Logs, screenshots, and evidence

Impact and severity

No response

Additional information

No response