claude-fable-5-1 real-task evaluations

Every report keeps its original task, method, finding, limitation, evaluator identity and verification date. A community report is evidence about that run, not a universal score.

  • Step 5 Preview and Claude Fable 5.1 on one front-end prompt

    By J A Z I I (@notjazii). X account that tests AI models and covers AI news Published 2026-09-20; retrieved 2026-09-24; verified 2026-09-24.

    Task
    Build a front-end page from a single prompt
    Method
    Same prompt at the highest available reasoning setting for both models; the author reported time and cost and repeated the Step 5 run without skills.
    Finding
    Claude Fable 5.1 took 40 minutes and $17 on the front-end prompt that Step 5 Preview finished in 10 minutes for about $0.50; the author left the quality comparison to readers.
    Limitation
    One prompt; the post leaves the quality comparison to readers rather than scoring it, and the cost gap follows each vendor's list prices.

  • Cortex AI: GPT-6 Astra, Gemini 3.8 Flash and Fable 5.1 on two real robot tasks

    By Cortex AI Research (@cortexairobot). Robotics team that builds real-world robot datasets and runs the MolmoAct2 real-world evaluations Published 2026-09-17; retrieved 2026-09-24; verified 2026-09-24.

    Task
    Load a sandwich into a microwave and close the door; attach a 5 mm tip to a pipette
    Method
    Each model controlled a bimanual YAM robot through an overhead and two wrist cameras with depth images, at medium reasoning effort with up to 10 minutes per task; an evaluator scored each attempt with partial credit for completed steps.
    Finding
    Fable 5.1 scored 6.7% on the microwave task and 20% on the pipette task, behind GPT-6 Astra (80% and 70%) and Gemini 3.8 Flash (13.3% and 30%).
    Limitation
    The post does not say how many attempts each model had; scores are partial-credit judgements by the lab's evaluator, and the authors attribute the gap mainly to weaker depth perception in the lower-scoring models.

  • AI Coding Daily LLM Coding Leaderboard

    By AI Coding Daily (@AICodingDaily). Coding-model testing channel and website that runs its own leaderboard and sells premium tutorials and channel advertising Published 2026-09-24; retrieved 2026-09-24; verified 2026-09-24.

    Task
    Implement and harden production-shaped projects in several stacks, including a Laravel app, a Go service and a React/TypeScript app, from the same prompts
    Method
    Each model and reasoning setting is a separate row run in a coding harness, with the average cost and time per run. Code quality is graded by a judge model against a published 100-point rubric and scaled to 20 points per project; behavioural reliability runs each of four projects five times and scores the checks every attempt fails.
    Finding
    Claude Fable 5.1 at medium reasoning scored 53.63 ($1.53 and 3 min 6 s per run in Claude Code), sixth of 47 rows, behind Claude Opus 5.5 and GPT-6 Astra.
    Limitation
    One author's benchmark whose code-quality half is graded by a judge model; rows run in different harnesses, the page is updated as models are added (read on 2026-09-24, 47 rows), and the author sells premium tutorials and advertising.