Claude Code now reads AGENTS.md when a project has no CLAUDE.md

Claude Code can now read a project's AGENTS.md file when no CLAUDE.md is present, one of several changes in version 2.1.277 of the tool, released on September 18, 2026.

What changed

According to the changelog, in a project with no CLAUDE.md, Claude Code reads AGENTS.md instead. The setting is changed under "Project instructions" in the /config command, so teams can see which file the agent picks up. The feature is not yet available on Bedrock, Vertex or Foundry, the hosted model platforms the tool supports, so users there keep the previous behaviour.

AGENTS.md is a Markdown convention that several coding agents use to hold project instructions, and until now Claude Code only looked for its own CLAUDE.md file. Teams that already keep an AGENTS.md for other tools had to duplicate the instructions; the new fallback removes that duplication, while an existing CLAUDE.md still takes precedence, since the changelog describes AGENTS.md as the file read when CLAUDE.md is absent.

The rest of the release

The same version adds CLAUDE_GATEWAY_PROXY_IS_EGRESS_BOUNDARY=1, an environment variable for Claude apps gateways whose only route out is a forward proxy: every outbound request hands the proxy a hostname instead of resolving it locally. An optional headers map on gateway upstreams lets administrators send static headers to a proxy in front of a provider, and background tasks now show a line when their update is waiting while a panel such as /tasks is open.

A long list of fixes accompanies the features. Sessions started with claude -p or the Agent SDK could hang with no result after an internal error; they now report the error and exit with code 1. Conversations could fail every request with "text content blocks must be non-empty" when an earlier assistant turn held an empty text block. Users could be unexpectedly logged out when an older build, such as an IDE extension's bundled CLI, ran on the same machine. Update checks errored every 30 minutes when a proxy returned an invalid version, and claude update on winget- or apk-managed installs reported "up to date" when the version lookup failed. The Grep and Glob tools reported no matches when a search could not start because the system was out of processes, memory or file handles; they now return an error saying so. The Write tool silently ended the turn as a declined permission when the target path was an existing directory.

A day later: auto mode on the server

Version 2.1.278, published on September 19, changes auto mode for Claude API and Enterprise users, and on Bedrock, Vertex, Foundry and gateways, to default to the server-side classifier, which does not charge for classifier overhead; CLAUDE_CODE_AUTO_MODE_SERVER=0 opts out on Bedrock, Vertex, Foundry and gateways, and a billed fallback now warns. A new Auto mode server row in /status shows whether the session's classifier runs on the server.

The changelog page is generated from the CHANGELOG.md file on GitHub, and the installed build can be checked with claude --version.