Fallbacks parameter now supports default mode per refusal category

July 24, 2026Claude PlatformView original ↗

1 feature

The fallbacks parameter now supports a "default" mode, which applies Anthropic's recommended fallback models by refusal category. Server-side fallback is in beta and requires the server-side-fallback-2026-07-01 beta header. See Refusals and fallback documentation.

More from Anthropic

Mid-conversation tool changes now in beta on multiple modelsJul 24, 2026
Mid-conversation tool changes beta for Fable, Mythos, Opus models
Mid-conversation tool changes are now in beta on Claude Fable 5, Mythos 5, Opus 4.8, and Opus 5, allowing tools to be added or removed betw…
Anthropic · Claude Platform
v2.1.219Jul 24, 2026
Claude Opus 5 is default; sandbox allowlist; nested subagents
Claude Opus 5 becomes the default Opus model with 1M context, and a new sandbox.network.strictAllowlist setting denies non-allowlisted host…
Anthropic · Claude Code

From other products

Fetched July 28, 2026

Fallbacks parameter now supports default mode per refusal… — releases.sh