Background Coding Agents: Predictable Results Through Strong Feedback Loops (Honk, Part 3)
Dec 1, 2025Max Charas (Senior Staff Engineer) and Marc Bruggmann (Principal Engineer)

Summary
Introduced background coding agents ('Honk') for automated software maintenance. Designed a verification loop with independent verifiers (e.g., Maven, build, test) that abstract away complexity and provide incremental feedback to the agent. Implemented an LLM judge to veto functionally incorrect or out-of-scope PRs, vetoing ~25% of agent sessions and leading to course correction in ~50% of those cases. The agent operates in a sandboxed environment with limited permissions for predictability and security.
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