Microsoft Open-Sources Agensh: A Multi-Agent Harness for 1,024 Agents
Microsoft Research has open-sourced Agensh , a decentralized harness for large teams of coding agents. The Agensh multi-agent harness removes the central orchestrator that most agent frameworks depend on. Every worker picks its own sub-task, shares findings and merges code into a common Git repo. On ProgramBench, the team scaled the setup from 1 agent to 1,024 agents. TL;DR A Harness : Tested from 1 to 1,024 agents. Each worker gets a 272,000-token input and 128,000-token output limit. Runs on: Linux with Docker Compose. Single node by default (8 workers). The 1,024-agent run used 16 nodes, 64 agents each. Workers have a 64 GiB memory ceiling. Performance: more agents raised scores on all 5 hardest ProgramBench tasks, and reached them sooner. Best: 79.59% pandoc pass rate with 32 agents on GPT-6.1-sol. GPT-5.6-sol hit 55.06% with 1,024 agents. Worst: the 5-task mean reached only 28.78% at 128 agents. Going from 1 to 8 agents added 1.37 points. What is...
