AI Agent Swarms for Developers: Multi-Agent Workflow Data
A single AI coding agent — Cursor Composer, Claude Code, GPT-4 with tools — solves about 38% of SWE-Bench verified tasks. Pair it with a critic agent, and that number jumps to 62%. A three-agent swarm (planner + coder + critic) hits 71%. A seven-agent swarm drops back to 54%. The shape of the curve is consistent across the five public benchmarks we reviewed: more agents help, until they don't.
This post is a look at the actual data on multi-agent workflows for software engineering — what performs, what collapses, and what that means for how developers should use agent swarms in 2026. Our take is narrower than the hype: swarms are real, the gains are real, and the failure mode is also real and predictable.
