FrontierCode 2.0
Cognition's FrontierCode 2.0 is a rebuilt 132-task agentic coding suite (FrontierCode 1.1 had 150 tasks) with updated scope grading. Tasks come from real open-source pull requests. The official score is a mean@5 composite of functional and rubric criteria measuring whether an agent produces a mergeable patch. Scores are not comparable with FrontierCode 1.1 Main or Extended (frontiercode-main / frontiercode-extended) and must not be restamped onto those slugs.
Models ranked
1
tracked on this benchmark
Score band
49.1 – 49.1
best → lowest tracked
Snapshot trend
—
need ≥2 snapshots
Leaderboard
Tracked models ranked by Mean@5 score (higher is better).
Configuration: claude-fable-5-2 (XHigh)
Notes: Cognition official FrontierCode 2.0 board (https://cognition.com/frontiercode, retrieved 2026-11-09): JSON-LD ListItem position 1, name 'Claude Fable 5.2', description 'Score 49.1%'. The Anthropic system card §8.4 confirms Cognition ran the evaluation (official eval, no changes), 132-task rebuilt suite (FrontierCode 1.1 had 150) with updated scope grading — scores are not comparable to frontiercode-main (1.1). Mean@5 composite. Effort peak is xhigh 49.1%; other Cognition/card efforts: low 34.2, medium 37.6, high 45.3, max 45.7 (max includes 22/660 timed-out attempts still graded; if timed out as zero, 44.4%). Claude models run in Claude Code. Highest-scoring published effort selected. This is an owner-board row on a NEW slug; it must not be written onto frontiercode-main. A /best/agents key move from FrontierCode 1.1 Main to FrontierCode 2.0 would put Fable 5.2 first at 49.1 and is a separate FE PR, not this packet.
How to read this benchmark
This benchmark scores models where higher is better. Use scores for directional filtering and shortlisting, not universal quality ranking; then validate pricing, context window, provider availability, and fit for your workload.
Trust this score when
- There is a fresh timestamped snapshot (or multiple snapshots) for this benchmark.
- The model list covers the same version family you can actually deploy today.
- Top candidates overlap with your required routing and feature requirements.
Be cautious when
- There is only one benchmark snapshot or the dataset appears stale.
- The benchmark metric direction is opposite of your decision objective.
- The score difference between options is narrow and likely within implementation variance.
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Last reviewed: Nov 9, 2026