Give Your AI Models Proven Skills
Skills are not just SKILL.md ✗ files. You can uplift any LLM model's performance by up to 20% with lab-tested ✓ skills.
You create SKILL.md for AI models.
But never test them.
Don't trust skills blindly. They can degrade LLM models and you won't know it.
the model's performance?
better than the last?
on your skill?
self-improvement capability?
in all harnesses?
the best skill version?
You shipped it anyway.
Create, test and run benchmarks on your skills
Skills can uplift an LLM model by 15%, but only tested skills do. The lab tests every draft, fixes what fails, and saves it as a new version — v1, v2, v3 — until the skill is good enough to ship.
Every skill version gets a score.
The lab creates the eval cases, then runs tests on your target model and scores your skill's performance. It keeps refining and testing the skill until the score passes 90. Only that version ships.
Test. Refine. Re-run.
The lab creates a self-improvement loop: it runs the skill, tests it against the eval cases, and fixes what fails. Each pass becomes a new version. The loop continues until the lab hits its goal.
- +40points better than the model with no skill
- 10/10eval cases passing before it ships
- v10the first version to pass 90. Earlier versions never leave the lab
No skill ships on trust. Every release is benchmarked on custom eval cases — base model vs the tuned skill.
Every skill version, on file
The lab keeps every skill iteration stored in the dashboard, so you can see which changes made a performance difference.
Take it anywhere, in one click
Export the final version or any version from the lab. Run your tuned skill in any harness with any model.
Your tuned skill is proven to perform better than the base skill.
Runs in every major AI coding tool
An open letter from the founder:
skills are systems, not prompts.
We switch to a bigger model or start fine-tuning when we want better results on our custom workflows. In most cases neither is needed. A well-structured skill can lift any LLM model's performance by up to 20%, with no fine-tuning at all. I tested this with 500+ skills and 20+ models.
In our testing, a model with a tuned skill beats the same base model on both performance and cost. It hallucinates less, burns fewer tokens on silly errors and gets the task done faster with better output quality.
I built skilltune to measure what a skill actually does. The lab writes custom evals from your description, runs them on your target model, and scores every version of the skill. The result is evidence: exactly how much better your model performs with the skill than without it.
Most skills are written once and never tested with any eval cases. Don't trust them blindly. Test your skills so you can use them in your daily workflows with confidence.
Skills are the most underused layer of the AI stack. The skilled models era is here. This is just the start.
Create a lab-tested skill in four steps
You describe the skill and answer a few questions. The lab creates it, tests it and hands you the lab-tested skill with a full report.
Describe or import
Write what the skill should do, or upload a SKILL.md you already use. Plain words are enough. The lab asks about the rest later.
- Start from a prompt or an existing SKILL.md
- No format to learn. Just describe the job.
Pick where it runs
Pick the harness and the model your skill has to work in. Then connect the Claude or ChatGPT subscription you already pay for. Tuning runs on your plan, with no separate API bills.
- Works with Claude Code, Codex, Cursor, opencode and more
- No API keys. Runs on your subscription.
The lab fills the gaps
The lab reads your request and asks about anything missing: edge cases, tone, boundaries. Then it writes v1, runs the eval cases and scores it. That score is your baseline.
- Clarifying questions before any tuning
- v1 scored right away, your starting line
What exact outcome should this skill produce?
Describe the job to be done and what a successful result looks like.
Who will use this skill, and where does it fit in?
Name the primary user, their expertise, and when they invoke it.
The loop runs until it passes
The lab tests the skill, fixes what fails, and saves the result as a new version. A version stays only if it scores higher than the last one. When a version passes the target score, tuning stops. You get that SKILL.md file, its score graph and the final benchmark.
- Score graph for every version
- Final benchmark vs the base model
- Portable to any harness, any model
One plan. Everything included.
No tiers, no monthly subscription, no add-ons. Every feature is included, with 12 months of regular updates.
Everything in skilltune.dev
- Create or improve unlimited skills. No rate limits.
- No credits, no API keys.
- Runs on your Claude, ChatGPT or opencode subscription.
- Everything stays on your machine. Full privacy.
- One-click export to any AI coding tool
- Works with open source LLM models
- Access to exclusive skills
- 12 months of product updates
- Priority support from the team
One plan, solo or team. Cancel in one click. Every skill you created stays yours.
Questions, answered straight.
The short version of everything people ask before claiming a seat.
Something else? hello@skilltune.dev
01What exactly is a skill?
A SKILL.md file — instructions, examples, guardrails and evals that teach an AI agent to do one job well. It's not just a text prompt but a complete system with scripts, assets and output instructions. With skills you can uplift the base model's performance by up to 20%.
02How does the lab test my skill?
The lab creates eval cases from your description and locks them before tuning starts. Every version runs the same tests and gets a score against the base model. A version stays only if it scores higher than the last one. When a version passes the target score, tuning stops.
03Do I need to write evals myself?
No. The lab drafts the tests from your description; you review and approve them before any tuning starts. Once approved, they're immutable.
04Can I bring a skill I already use?
Yes. Upload your SKILL.md and the lab benchmarks it, then tunes it version by version until we reach the best version.
05Which AI coding tools and models does it work with?
All the major ones. Your tuned skill exports in one click and runs in Claude Code, Codex, Cursor, opencode or any other AI coding tool. Open source LLM models work too.
06Is my work private?
Yes. Your skills, versions and eval results are stored on your machine. Nothing leaves it.
07What happens after the first 500 seats?
The price moves to $199/year. Early birds keep the $149/year rate for as long as they stay subscribed. You can cancel anytime, in one click, but you won't, cuz you'll love it.
08Who owns what I build?
You do. Every version of every skill is yours to export, self-host and ship — including after you cancel. We do not store any of your skills or drafts on our servers.
Create lab-tested skills and use them anywhere.
The end-to-end skill pipeline in one place: create, test and export. Tune your skills with skilltune.
$149/year early-bird · every version on file · runs in Claude Code, Codex, Cursor, opencode