alt Hacker NewsOpus is still first in Intelligence Index followed by Fable, GPT 5.6, Kimi K3 then Qwen 3.8 max. https://artificialanalysis.ai/#intelligence
Our leaderboard combines Arena ELO, AA Intelligence index, latency and speed and goes: #1 Opus 5 #2 Kimi K3 #3 Qwen3.8 Max #4 GPT 5.6 Sol
Source: http://pellmell.ai/leaderboard.
This jumps around a lot based on the top throughput and latency of whatever provider happens to be best at the moment.
All these "intelligence" benchmarks miss something extremely important when using an LLM in a code-agent harness: How it communicates with you about what it did.
Opus-5 is practically unusable (for complex tasks) in this sense - its updates are voluminous, and dense with cryptic language (there are numerous reddit threads complaining about this, so it's not just me). I often have to ask it to re-state concisely in plain terms.
For a fairly gnarly task, after fighting with with Claude-Code + Opus-5, I ported my session to Codex + GPT-5.6-sol, and it was like a breath of fresh air.
Arguably a key aspect of intelligence is concise, clear communication, and current benchmarks miss that, at least as far as I'm aware. I would think some arena-type benchmarks where humans rate responses would measure this, though I'm not sure which those are.