Claude Code merged support for OSC 7501

Anthropic's Claude Code v2.1.295 added support for OSC 7501 (program status), a terminal escape sequence that reports an application's status, according to a post by Mitchell Hashimoto on X. Hashimoto said the protocol support "will help hundreds or thousands of downstream applications" and that Anthropic verified it works through Rex, a tool he referenced. A commenter offered to commit to adding OSC 7501 support to their own harness within 4 hours of receiving Rex beta access.

Mitchell Hashimoto on X: "Claude Code v2.1.295 supports OSC 7501 program status . Incredible speed @AnthropicAI supporting this protocol which will help hundreds or thousands of downstream applications They had access to Rex and verified through Rex it works. 🥰" Claude Code v2.1.295 supports OSC 7501 program status . Incredible speed @AnthropicAI supporting this protocol which will help hundreds or thousands of downstream applications They had access to Rex and verified through Rex it works. 🥰 Claude Code v2.1.295 supports OSC 7501 program status . Incredible speed @AnthropicAI supporting this protocol which will help hundreds or thousands of downstream applications They had access to Rex and verified through Rex it works. 🥰 Yeah this is great can I get access to Rex to make sure OpenCode works through it, don't worry about contacting any of my coworkers you can just contact me I will commit to turning around OSC 7501 support in my harness within 4 hours of getting access to the Rex beta. My harness has 1 user but we're growing fast.