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Claude skills

Claude skills, with real execution behind them

A Claude skill teaches Claude how to do a job the same way every time. Pair it with UniversalBench and the steps that run code, query a database, search the live web, or commit to a repo run through one hosted MCP URL, with safety built in. Connect once in Claude and your skills gain a place to do real work.

Skills are the recipe. The work still has to run somewhere.

A skill is a folder with a SKILL.md file: instructions, and often a few small scripts, that teach your AI how to do a job the same way every time. That is the recipe, and a recipe is not a kitchen. The moment a skill needs to run code, read a database, call the live web, or commit to a repo, that work has to execute somewhere, and you want it to run safely. MCP is how your AI reaches those tools. UniversalBench is the hosted place the work actually runs. The skill is the recipe, MCP is the wire, and UniversalBench is the kitchen.

See it in action

# A weekly-numbers skill You: "Run the weekly-numbers skill." the skill loads, then calls UniversalBench: query the database (Postgres) run the analysis in code (code) return a clean summary (only the rows you asked for come back)

Skills run code, so the runtime matters

Anthropic is blunt about this in its own guidance: a skill can direct your AI to run code or call tools in ways that do not match its stated purpose, so you should only run skills you trust. When a skill’s steps run on UniversalBench, three checks are always on. Code is validated and confirmed to load before it is ever committed. Every model call is cost estimated and capped before it runs. No request can reach a private or internal network address. The work gets done without handing a skill the keys to everything.

Connect UniversalBench

Open Connectors

In Claude, go to Customize, then Connectors. Works on the Free, Pro, Max, Team, and Enterprise plans.

Add a custom connector

Click the plus, choose Add custom connector, paste your UniversalBench MCP URL, and save.

Add your skill

Upload or add your skill in Claude settings as you normally would.

Ask Claude

When a skill step needs to run code, query a database, search the web, or commit, Claude runs it through UniversalBench.

# your UniversalBench MCP URL https://universalbench-mcp.penantiaglobal.workers.dev/u/<your-key>

Credentials live in an encrypted secret vault

When a skill’s step needs a credential, a GitHub token, a database URL, an API key, you save it once in your secret vault. You enter the secret name on the left and the secret value on the right, then save. Your AI never sees the value, it is never shown in the chat, and the matching capability unlocks automatically.

UniversalBench secret vault: the secret name on the left, the secret value on the right, then save
Any secret goes in your secret vault once: the secret name on the left, the secret value on the right, then Save.

A skill alone versus a skill with an execution layer

Skill on its ownSkill plus UniversalBench
What it gives the AIInstructions and small scriptsInstructions plus real execution
Run code, query a database, hit the webOnly if the host provides itOne hosted URL covers all of it
Reach your toolsDepends on the surfaceGitHub, Postgres, Slack, Sheets, and more
Safety on the workUp to you to auditValidated code, capped spend, no internal network
CredentialsIn files or promptsEncrypted vault, never shown

Frequently asked questions

Do Claude skills require this?

No. Claude can run many skills on its own. Pair UniversalBench when a skill needs your database, the live web, your GitHub, any model, or stronger safety on the code it runs.

Does it work across Claude.ai, Claude Code, and the API?

Yes. Connect the one hosted MCP URL on whichever surface you use. Skills are managed per surface, the execution layer is the same.

Is it free to start?

Yes. The first 1,000 calls each month are free with no credit card, then it is pay as you go.

Is this made by Anthropic?

No. Claude and Claude skills are Anthropic. UniversalBench is an independent hosted MCP server you connect to Claude.

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Add real execution to your Claude skills

One URL, first 1,000 calls free, no credit card.

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