# Skills and connected tools

Open **Settings → Marketplace** to add optional instructions and tools to Syntheo.

## Skills

A Skill is a reusable set of instructions for a particular kind of work.

Use a Skill when:

- the same process comes up often;
- a task needs a consistent checklist;
- your organization has an approved workflow;
- you want the procedure to be reviewable and reusable.

Before installing a Skill, review its source, files, purpose, and requested actions.

### Choose how a Skill is used

- **User invoked:** the Skill is available only when you select it with `@`.
- **Model invoked:** Syntheo may choose it automatically when it seems relevant.

Start with User invoked. Switch to Model invoked only when the Skill is trusted, broadly useful, and clearly described.

## Connected tools and MCP

A connected tool gives Syntheo access to another app, service, or local capability. MCP is the connection standard used by many of these tools.

Use a connected tool when Syntheo genuinely needs an external capability, such as looking up approved information or interacting with another service.

After adding a connection:

1. Refresh its available tools.
2. Read each tool's name and description.
3. Open **Settings → Permissions**.
4. Keep unfamiliar, write-capable, or sensitive tools on **Ask**.
5. Test with a small, reversible request.

## Choose when tools are visible

- **User invoked:** select the tool with `@` for the current turn.
- **Model invoked:** Syntheo may discover and use the tool automatically.

Use User invoked for production systems, communication tools, paid services, or anything with broad access.

## Safety checklist

- Trust the source and publisher.
- Understand which account, files, or service the tool can access.
- Use the narrowest available credentials.
- Read approval details before allowing writes or external actions.
- Remove connections you no longer use.
- Refresh tools after an update so their descriptions stay current.

## Which should I use?

| Need | Use |
|---|---|
| One-time instructions | A prompt |
| Reusable procedure | A Skill |
| Access to another service or capability | A connected tool |
| Stable project rules | Project instructions |
| Personal response preferences | Behaviour settings |

[← Tool permissions](permissions.md) · [Settings and safety](README.md) · [Next: Help and reference →](../reference/README.md) · [Documentation use notice](../NOTICE.md)