Claude Opus 4.8: Benchmark Results and Review

Claude Opus 4.8 Review and Benchmark resultsKey insight: 10.6-point gap on SWE-bench Pro is the largest between Opus 4.8 and GPT-5.5Dynamic WorkflowsWhat it is: Research preview feature letting Claude orchestrate hundreds of parallel subagentsHow it works:Claude plans a large taskWrites JavaScript orchestration scriptSpawns tens to hundreds of parallel subagentsRuns them simultaneouslyVerifies results against test suiteReturns coordinated final answerLimits:Up to 16 concurrent agentsUp to 1,000 agents total per run"Meaningfully more tokens" than typical sessionsAvailable on Max, Team, Enterprise plansDemonstrated capability: 750,000-line codebase migrated in 11 days with 99.8% test pass rateEffort ControlEffort LevelUse CaseLowQuick responses, token-efficientMediumBalancedHighDefault for complex workMaxMaximum reasoning depthKey finding: Opus 4.8 at minimum effort matches Opus 4.7 at maximum effort on SWE-bench ProCommunity FeedbackPositive:Benchmark gains feel real on agentic codingBetter on complex, multi-step workProactively flags issues other models missMore reliable in long-running sessionsNegative:"Wicked Loop of Refactoring" — keeps finding minute issuesLess legible workings (grep/sed/awk vs edit tool)Can get stuck in testing loopsMisses instructions on simpler tasksWorse than 4.7 on some UI generation prompts Hosted on Acast. See acast.com/privacy for more information.