K3 is a frontier quality open model at a fraction of the cost. Even bigger is that it complements Fable predictably, which makes it possible to get the highest quality intelligence by routing tasks. 🧭 tl;dr: We ran Kimi K3 (open) against Fable 5 (closed) on ~1,000 agentic tasks finding: We achieved 93% accuracy with routing between K3 and Fable. Results were up to ~50X more cost effective than Fable alone on long agentic loops, and consistently lower cost across every use case. How We Measured We averaged benchmarks, each aimed at a different kind of work , and ran K3 and Fable 5 through the same harness. About 1,030 tasks in all, in real agent loops. Family What it tests Tasks SWE Real repo bug-fixes (SWE-bench style) 460 Terminal Long agentic ops: security, crypto, reverse-eng, sysadmin 89 Algorithmic LeetCode / AtCoder-style problems 100 Multi-Language Implementation across six languages 225 Legal A legal-agent benchmark (lawyer-graded tasks) 120 One quick definition before we get into the results.…