---
title: "Registry: MCP"
description: "What a registry has to serve for the newtui MCP server to browse, search and install from it."
---

The [MCP server](/docs/mcp) answers from whichever registry the project's
`components.json` names. Point that at your own registry and every tool follows
— there is nothing extra to configure.

```json title="components.json"
{
  "registry": "https://acme.dev/r"
}
```

## What the tools need [#requirements]

| Tool                                | Reads                                                          |
| ----------------------------------- | -------------------------------------------------------------- |
| `list_items_in_registries`          | `/index.json`                                                  |
| `search_items_in_registries`        | `/index.json` — matched against `name`, `title`, `description` |
| `view_items_in_registries`          | `/styles/<style>/<name>.json`, with `files[].content`          |
| `get_item_examples_from_registries` | index entries of type `registry:example`                       |
| `get_design_tokens`                 | `/styles/<style>/theme-newt.json`, with `cssVars`              |

Two of those are worth stating plainly, because a registry that omits them
still installs fine from the CLI and reads as empty to an agent:

- **Give every item a `title` and a `description`.** They are what search
  matches on and what an agent uses to choose between two components. An item
  with neither can only be found by knowing its name already.
- **Ship your examples.** An item of type `registry:example` named
  `<component>-demo` is what `get_item_examples_from_registries` returns. It is
  the shortest correct usage of the component, and it is what stops a model
  inventing a prop.

## Tokens [#tokens]

`get_design_tokens` reads the `registry:theme` item named `theme-newt` and
returns its `cssVars`. A registry that extends newt/ui usually re-serves that
item unchanged; one that replaces the palette serves its own values under the
same item name, and every answer the agent gives follows the new palette.

See [registry-item.json](/docs/registry/registry-item-json#theme) for the shape.

## Checking it [#checking]

```bash
curl -s https://acme.dev/r/index.json | head -40
npx newtui@latest search --registry https://acme.dev/r
npx newtui@latest view button --registry https://acme.dev/r
```

If those three answer, the MCP tools will too — they read the same two files.