> ## Documentation Index
> Fetch the complete documentation index at: https://docs.decimal.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Install a Skill in 5 Minutes
> Tutorial: pick a skill with a verified benchmark from the public registry, install it into Claude Code or Cursor, and watch it fire — no signup, no SDK, no API key.
You use Claude Code or Cursor. This tutorial installs one skill from the public registry — a skill with a *measured, verified* benchmark, not just stars — and shows it firing in your next session. No account, no SDK, no API key, under 5 minutes.
A **skill** is a `SKILL.md` file: instructions your agent reads when a matching task comes up (a triage policy, an extraction schema, a commit-message convention). It's an open format your runtime already understands — DecimalAI's registry adds the part no file format can: **evidence that the skill actually works**.
Open the skill's public page — no login:
**[app.decimal.ai/skills/playwright-cli](https://app.decimal.ai/skills/playwright-cli)**
Before installing anything, read the two surfaces that make this registry different:
* **Verified lift** — at the time of writing: **+79 points**. With the skill loaded the benchmark agent passed **24 of 24** cases; without it, about **21%** (5 of 24). That's a with-vs-without A/B run (an *ablation*) executed by the hosted runner, not self-reported by the author — and the live scorecard, not this page, is the canonical copy of today's numbers. `never_hurt` means no case got *worse* with the skill loaded — here, zero regressions.
* **The fine print that keeps the number honest** — the model it was measured on (`gemini-3.6-flash`), the benchmark date, the grading method (LLM-judged against per-case expectations), and the **cost**: at the time of writing this skill spends about **126% more tokens** for that lift, because it puts a command reference in the prompt. Lift is model-relative and never free; the registry shows you the evidence instead of asking you to trust a score.
* **Two different axes, one page** — you may see a SkillScore marked *provisional* right next to a *verified* benchmark. Not a contradiction: *provisional* describes the composite [SkillScore](/guides/skillscore) (it rests on a single signal so far), while *verified* describes how the benchmark itself was produced (executed by the hosted runner rather than self-reported).
Also check the **safety band**: this skill is **Passed** — a static scan (secrets, remote-code execution, hidden unicode), an AI intent review, and a content review all came back clean. [How skills are vetted](/guides/trust-safety/how-skills-are-vetted) covers what that does and doesn't guarantee.
Why this skill for the demo: `playwright-cli` documents one specific tool's exact flags — and a model that has never seen that tool mostly cannot guess them. That is why the no-skill arm passes only about one case in five, and it is why you can *tell* the skill fired: the answer either contains the right flag or it doesn't. It's a worked example of the general pattern — skills earn lift by supplying knowledge the model can't have.
**Prefer to stay in your editor?** Once, in any MCP client:
```bash theme={null}
claude mcp add decimalai -- uvx decimalai-mcp
```
Then read the same scorecard by asking — *"show me the benchmark evidence and safety scan for playwright-cli"* — instead of opening the page. It's read-only, so you still install with the commands in the next step. See [Use skills without the SDK](/guides/use-skills-without-the-sdk#mcp-server).
Both routes are anonymous and end in the same place: a `SKILL.md` on disk where your runtime auto-discovers it.
The DecimalAI CLI pulls skills anonymously — no API key:
```bash theme={null}
pip install decimalai
decimalai skills pull playwright-cli --out .claude/skills/
```
Writes `.claude/skills/playwright-cli/SKILL.md` — plus the skill's `eval.yaml` test suite, so you can [re-run the benchmark yourself](/guides/skillevaluation). Read-only: no fork is created, nothing is tracked.
On the [skill's page](https://app.decimal.ai/skills/playwright-cli), use the **Copy SKILL.md** button and paste into a new file at `.claude/skills/playwright-cli/SKILL.md`. The copy arrives with `name` + provenance frontmatter already stamped — add a `description:` line (your runtime discovers skills by `name` + `description`) so the final block reads:
```yaml theme={null}
---
name: playwright-cli
description: Automate browser interactions, test web pages and work with Playwright tests.
source: https://app.decimal.ai/s/playwright-cli@/SKILL.md
source_sha256:
---
```
`` and `` are placeholders — your copy arrives stamped with real values that track whatever version is current when you copy. The `source` / `source_sha256` lines are the provenance stamp — the Copy button and the raw-URL route add it automatically (`decimalai skills pull` does not); it records where the file came from and a fingerprint of the exact body you copied. The fingerprint recipe: the first 12 hex characters of the SHA-256 of the skill body — whitespace-stripped, frontmatter excluded, hashed *before* the stamp itself is added. Optional but worth keeping: see [Use skills without the SDK](/guides/use-skills-without-the-sdk#provenance-the-source-stamp).
Start a **new** Claude Code (or Cursor) session in the project — skills are discovered at session start. Then paste a task the skill was built for:
```text theme={null}
I'm on Windows using cmd.exe. Give me the exact playwright-cli command to
open https://example.com/search?q=shoes&sort=price&page=2
```
`cmd.exe` treats `&` as a command separator, so an unescaped URL gets truncated at the first `&` and the command silently does the wrong thing. The skill documents the fix: escape it as `^&` in `cmd.exe` (or use `--%` in PowerShell). Nothing about that is guessable — it's one tool's documented quirk.
**What you should see:**
* The transcript shows the agent reading the skill (Claude Code surfaces the skill it loaded, or you'll see it open `.claude/skills/playwright-cli/SKILL.md`).
* The URL in the answer escapes each `&` as **`^&`** — `...?q=shoes^&sort=price^&page=2`.
* If you get the raw unescaped URL instead, the skill didn't load: check the file path and frontmatter, start a fresh session, or name it explicitly — "use the `playwright-cli` skill."
## What just happened
You installed a plain-markdown skill your runtime already knows how to read, and you picked it off a scorecard instead of a download count. You also saw the shape of the trade: at the time of writing, the skill bought +79 points of correctness by spending a bit over twice the tokens. Both halves are on the scorecard — that's the point of measuring rather than starring.
## Next steps
Web copy-paste, CLI pull, raw URLs, and the MCP server — every route from the registry to your agent, one page.
Assemble a customer-operations agent from measured registry skills — and wire it so usage counts.
Every published skill, ranked by measured effectiveness. No login to browse.
skillevaluation is the open spec + runner behind every verified lift number. Re-run any benchmark yourself.