AI Coding Benchmarks Lie: What Scores Actually Hide

Direct answer: No public benchmark currently ranks AI coding assistants reliably on speed, accuracy, and cost together.

Accuracy scores depend on who ran the test and on the tool wrapped around the model. Cost is set by the billing model and retry rate, not by the seat price. One model, the same benchmark, and two numbers 28 points apart.

Key takeaways

• Anthropic’s system card puts Claude Opus 5.5 at 89.9% on SWE-bench Pro, and the October 2026 BenchLM leaderboard repeats it.
• Cost: the seat price is the smallest part. List prices as tracked by Developers Digest, verified September 28, 2026.
• Tool B spends $90 over 20 merged changes at 4 minutes each.

Give each assistant the same ticket text, the same starting commit, and the same time limit.

Read the full article: https://www.trendix.tech/ai-coding-benchmarks-lie/