Coding agents finish 95% of single requests but only 51% of 20-request chains
BOBA-Bench strings 20 consecutive requests from 140 real open-source projects into 280 chains and tests ten coding agents. They complete 95% of requests one at a time but 51% when chained, because an agent calls a request done once its own tests pass and the next request builds on the missed mistake. Reviewing code, agents judge correctness right 53% of the time. One outside signal that a request failed, plus a repair round, lifts chain completion to 59%.