Learning Design from Mature Coding Agents (21): Headless Mode and CI Usage — When Nobody Can Click Approve
The biggest problem when an agent enters CI is approval: no TTY, nobody to click approve. The five reference projects converge on two strategies — delegate permission decisions to the calling program (claude-code's control protocol), or replace approval semantics entirely (codex defaults to Never plus sandboxing, opencode auto-rejects). rivumi keeps one AgentRunner loop and injects a different ApprovalPolicy: headless uses HeadlessApprovalPolicy, which never reads stdin so it cannot hang the pipeline, and denies EXECUTE by default — fail closed.