Daily · · Claude Code · 🌶️🌶️Worth a lookMedium: worth a look Why: Default prompt changed
Claude Code: Shorter prompt for custom models
Claude Code quietly shortens the prompt for custom model names.
On Bedrock, Vertex, Foundry and Mantle, names it doesn’t recognize, even ones that point at Sonnet or Haiku, now get the shorter system prompt. Set CLAUDE_ to keep the full prompt.
What changed
A custom name can quietly change how Claude Code talks to your model. That covers custom deployment names and inference profile ARNs, which Claude Code can’t match to a known model.
Also changes for unknown names
Automatic model switches after a flagged message now cover these names too. To turn those switches off, set CLAUDE_.
Also in this release
- Claude no longer overwrites a very large CLAUDE.md, rules file or @-included file in a subdirectory after seeing only its start. Write now asks it to read the whole file or edit in place.
- Prompt and agent hooks now run at most 24 at a time per session, plus 12 that have waited longer than their timeout. A timeout under 1 second counts as 1 second.
- The Claude apps gateway gets
oidc., for picking the user ID claim, like Entra ID’suser_ id_ claim oid. - Usage-limit messages now say “5-hour limit”.
What to do
Update Claude Code. If you run it under a custom model name and want the full prompt, set CLAUDE_.