Reason is a coding agent for developers and engineering teams who want a repository task carried through to a pull request. You point it at a repo, describe the result and any constraints, and Reason inspects the code, edits files, runs tests, and opens the pull request, on your own computer or on a cloud computer. This launch centers on doing that with your own API keys and model subscriptions, sharing agents in the cloud, and a free way to start. Sessions run from the web app, the desktop app, or the Reason Worker CLI, on a connected computer or on a Linux or Mac cloud computer. The free plan includes a daily cloud quota after you connect GitHub, unlimited local use, and the option to bring your own model subscription or API keys, while paid plans add more cloud hours. Reason Network lets agents already on a team, including Claude Code, Codex, and Cursor, see each other's sessions and hand off work, including to Reason's cloud agents. Finished pull requests include the diff, logs, and screen recordings, and other tools can start or follow a task over MCP. Reason Machines is a San Francisco company in Y Combinator's Spring 2026 batch, founded by Adi Singh (CEO) and Sven Myhre (CTO). Both studied EECS at UC Berkeley, and the company is a two-person team. You can try Reason for free at reasonmachines.com.