$npx skillfedfor your agent

Same skill, +22 points for Claude Sonnet, +5.5 for Nemotron Nano

Notes on A Framework for Evaluating Agentic Skills at Scale (arXiv:2606.17819) — Maksim Shaposhnikov, Nicolas Fortuin, Simon Stipcich, Maria I. Gorinova, Amy Heineike, Robert S. Willoughby · June 2026

Note published · written by SkillFed’s research pipeline from the paper above · how these notes are made

AI-assisted notes · reviewed by SkillFed Agentic benchmarks

An automated pipeline turns any agent skill into a battery of executable tests. It reads the skill's content, provisions whatever the task needs — CLI tools, credentials, a specific runtime — drafts a realistic task description, and writes two hidden scoring rubrics, then runs a validation pass to confirm the task doesn't leak its own answer. Applied to 500 real-world skills pulled from public registries and sourced from roughly 100 organizations, including Anthropic, Google, ElevenLabs, and Shopify, the pipeline generated about 1,000 tasks. Each one was solved twice — once with the skill available, once without — across 19 proprietary and open-source model configurations spanning Claude, GPT, Gemini, GLM, DeepSeek, Kimi, MiniMax, Qwen, and Nemotron. That produced roughly 38,000 scored trajectories, graded on two separate rubrics: did the output actually work (goal completion), and did it follow the skill's encoded conventions (instruction-following).

Skill access reliably moves the needle, but by wildly different amounts. The aggregate score gain — the skill delta — ranges from +5.5 points for Nemotron 3 Nano 30B up to +22.1 for Claude Sonnet 4.6, and it comes almost entirely from instruction-following: goal completion was already high without a skill and climbs above 90% for most models once the skill is present, Nemotron being the one holdout. Frontier instruction-following scores cluster in the mid-to-high 80s (Opus 4.8 at 88.0, Opus 4.7 at 87.7, the open-weights GLM 5.1 at 85.0), while Kimi K2.6, MiniMax 2.7, and Qwen3-Coder-Next sit 25-30 points lower even with the skill in hand. Give a cheaper model the skill and it closes in on its flagship sibling: GLM 5.1 hits an overall score of 91.1, within 1.2-1.6 points of Opus 4.7's 92.3 and Opus 4.8's 92.7, at roughly a quarter of the per-scenario cost. The uplift is domain-dependent too — skills that encode concrete step-by-step workflows, like media file processing or security checklists, gain over +30 points, while skills that mainly state general best practices, like testing or scientific computing, gain closer to +17.

Key numbers

Corpus scale500 skills → ~1,000 tasks → 19 models
Skill-driven score gain (range across models)+5.5 to +22.1 pts
Instruction-following gap: frontier vs. mid-tier models~25-30 pts
Kimi K2.6 skill delta (recent model, low uptake)+7.1 pts
Open-weight cost to near-match flagship quality$0.89 vs. $3.94/scenario

Skills related to this research

Related notes

References

  1. Shaposhnikov, Fortuin, Stipcich, Gorinova, Heineike & Willoughby (2026). A Framework for Evaluating Agentic Skills at Scale. arXiv:2606.17819
  2. Li, Chen, Liu et al. (2026). SkillsBench: benchmarking how well agent skills work across diverse tasks. arXiv:2602.12670
  3. Liu, Ji, An, Jaakkola, Zhang & Chang (2026). How well do agentic skills work in the wild: benchmarking LLM skill usage in realistic settings. arXiv:2604.04323
  4. Wang, Chang, Patel et al. (2025). MCP-Bench: benchmarking tool-using LLM agents with complex real-world tasks via MCP servers. arXiv:2508.20453