A code reviewer agent checks out pull requests, reads the diff in full, and publishes a structured review with inline comments, a summary of concerns, and an explicit approve or request-changes decision. It is distinct from a tech lead: the reviewer focuses on correctness, readability, and style compliance for each individual PR rather than cross-cutting architectural direction.
In Fleet, you configure a code reviewer using the pr-reviewer role (or tech-lead / qa-engineer), because review quality depends heavily on the prompt. A role-specific reviewer prompt encodes your style guide, the categories of bugs your codebase is prone to, and the threshold for blocking a merge. Without this, a generic agent produces superficial reviews that miss the class of issues your team actually cares about.