Anthropic AI Updates: September 20, 2026

1. Auto Mode’s Classifier Moved Server-Side by Default, and /status Now Tells You Which Side It Runs On

Anthropic released Claude Code 2.1.278, which adds an Auto mode server row to /status reporting whether the current session’s auto mode classifier runs on the server or locally. The row exists because the default changed underneath it: for Claude API and Enterprise users, and on Bedrock, Vertex, Foundry, and gateways, auto mode now uses the server-side classifier, which does not bill for classifier overhead. Sessions that fall back to the billed local path get a warning rather than silently accruing the cost, so the /status row is the way to confirm which behavior a given session actually got.

On Bedrock, Vertex, Foundry, and gateways the change is opt-out via CLAUDE_CODE_AUTO_MODE_SERVER=0. Anthropic documented the billing details at code.claude.com/docs/en/auto-mode-classifier-billing. Source