Grok 4.5 (xAI BYOK) fails with AI_TypeValidationError; Grok 4.2 works

[rawahi2]

Description

Summary

Grok 4.5 via BYOK xAI fails on every prompt with AI_TypeValidationError while parsing the Responses API stream. Grok 4.2 with the same key works.

Environment

• OpenScience version: openscience --version says 2.9.1 while the web interface shows 1.2.2!!!
• OS: macOS 26.5.1
• Install method: npm global
• Provider: xAI BYOK
• Model that fails: grok-4.5
• Model that works: grok-4.2

Steps to reproduce

1. Set XAI_API_KEY and start OpenScience.
2. Create a new session.
3. Select model grok-4.5.
4. Send any short prompt (e.g. "hello").

Expected

Normal streamed reply from Grok 4.5.

Actual

Immediate failure. UI may show empty / compacted context.

Plugins

No response

OpenScience version

No response

Steps to reproduce

No response

Screenshot and/or share link

No response

Operating System

No response

Terminal

No response