Polylane replaced its multi-agent autofix workflow with a single agent. The old system used up to 18 agents for triage, coordination, hypothesis testing, and coding. Context loss between agents led to poor pull requests and long resolution times. The new single agent performs all steps itself. Median resolution time dropped from 2.2 hours to 35 minutes. The p90 resolution time fell from nine days to under two hours. The share of issues ending in a pull request rose from 0.6% to 4.2%. Average cost per pull request fell from $111 to $18. Polylane attributes the gains to fewer handoffs and full context retention. It now advises against building sub-agent architectures.
What changed
Autofix used a workflow of up to 18 agents: a triage agent, a coordinator, up to 15 hypothesis sub-agents, and a coding agent.
What it unlocks
A single agent now handles triage, investigation, hypothesis testing, and pull request submission end-to-end.
- 2.2 hours to 35 minutes median resolution time
- 9 days to under 2 hours p90 resolution time
- 0.6% to 4.2% share of issues ending in a pull request
- $111 to $18 average cost per pull request
Sources