[production] Prism gpt-6.1-sol returns repeated 422 with v2.9.7 gateway and pr269 adapter

[ranxi2001]

Summary

The production gateway returns HTTP 422 for repeated gpt-6.1-sol Responses requests when the scheduler selects account 300 through the Prism adapter. Other models and the same account's gpt-6-sol traffic succeed.

Evidence

• Release: v2.9.7 / bc83ff9c367883e5b7d0140e6bb42e2e7cc5239c
• Prism adapter currently running: pr269-49b0f52
• Window: 2026-10-03 Asia/Shanghai, approximately 03:50–03:58
• 8 natural requests for gpt-6.1-sol, all selected account 300, all returned 422 within roughly 14–40 ms.
• Gateway error: prism adapter returned HTTP 422
• Example request IDs: 0b758ddc-3933-42b4-9dd1-12da6e3cace5, 3ffb2820-eebc-4301-b922-e957050c7a89
• Same window: gpt-6-sol requests completed with HTTP 200 on accounts 300, 446, and 447; gpt-6-astra and gpt-5.6-sol also completed successfully.

The failing traffic was user 338, API key ID 228, group ID 13; no credential or request body is included here.

Suspected deployment compatibility

The Go release includes the merged Prism bridge changes from PR #278, while the separate browser adapter remains on the earlier pr269-49b0f52 trial release. This may be an adapter/protocol or model capability mismatch rather than a generic upstream account failure.

The issue is filed for compatibility tracking because another change is already reported as fixing the Prism path. Please link the definitive fix and state the required Go/adapter pair and rollout order.

No new paid request was generated while investigating; the evidence is from natural production traffic.

[ranxi2001]

Additional deployment evidence:

• The owner release v2.9.7 includes the merged Go gateway work from PR #278, but production still runs the separate browser adapter release pr269-49b0f52.
• A read-only Nginx route probe confirms the explicit X-Sub2API-Node: nerd path reaches the gateway; no paid model request was generated during this check.
• Please link the already-available Prism adapter fix and document the compatible gateway/adapter release pair, including whether pr269-49b0f52 must be replaced before enabling gpt-6.1-sol on the gateway.