v0

v0 connects to ReUI through its MCP Connections, so you can build production UI from the ReUI registry right inside a chat. The endpoint is https://mcp.reui.io over Streamable HTTP, the same one every agent uses - see MCP Server for the shared background.

Connect ReUI

Name:           reui
URL:            https://mcp.reui.io
Authentication: OAuth

The ReUI skill

You do not install anything - the skill rides on the MCP from mcp.reui.io. Once the connection is authorized, v0 gets ReUI's tools and can call get_agent_skill to load the full ReUI workflow (the reuse-first rule and the discover, install, adapt order) as a document. If a build ever drifts off-pattern, tell it to "follow the ReUI skill" to reload that workflow.

Build with ReUI

Describe the interface you want in plain language and v0 pulls the right ReUI components, examples, and blocks from the registry, then wires them into your project.

Use ReUI to scaffold an admin app - the app-shell with a collapsible sidebar and top bar, and a dashboard page with stat cards and a chart.

Add a data-grid of orders with sorting, column filters, pagination, and row selection, wired to my /api/orders endpoint.

Build a multi-step "create project" wizard with the ReUI stepper and form components, with validation on each step.

Add a kanban board for support tickets with drag and drop, grouped by status, and a filters bar above it.

Unlock premium items

Free items (the 20 components and every c-* example) install with no license. Since v0 runs in the cloud, apply these steps inside the v0 project it is building, not on your local machine. To let v0 install premium blocks, icons, and templates too, grab a Pro or Ultimate license - one license unlocks the whole premium registry and removes the daily MCP request limit. Then add your key to the project - two quick steps:

REUI_LICENSE_KEY=your-license-key-here

{
  "registries": {
    "@reui": {
      "url": "https://reui.io/r/{style}/{name}.json",
      "headers": {
        "Authorization": "Bearer ${REUI_LICENSE_KEY}"
      }
    }
  }
}

That is it - v0 can now install any premium item the MCP returns, and free items keep working through the same config. See License Setup for the full guide, or compare plans on the Pricing page.

Headless and CI

v0 itself always runs in a browser, so the OAuth flow above is the normal path. When you provision chats through the v0 Platform API instead, register the server with a personal token from Account → MCP so no browser sign-in is needed:

curl -X POST https://api.v0.dev/v1/mcp-servers \
  -H "Authorization: Bearer $V0_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "reui",
    "url": "https://mcp.reui.io",
    "auth": { "type": "bearer", "token": "reui_pat_your_token_here" }
  }'

The same call through the v0-sdk package:

import { v0 } from 'v0-sdk';
 
await v0.mcpServers.create({
  name: 'reui',
  url: 'https://mcp.reui.io',
  auth: { type: 'bearer', token: process.env.REUI_MCP_TOKEN! },
});

Tokens expire after 90 days by default (30, 60, 90 and 180 are offered, plus No expiry for pipelines that cannot rotate). Nothing emails you beforehand, so an expired token simply starts returning 401 - create a fresh one at Account → MCP and update the server. Existing tokens keep whatever lifetime they were issued with.

Troubleshooting

Almost every hiccup is a stale sign-in - the fix is to reconnect and authorize again. The one exception is a personal token, which cannot be re-authenticated and has to be replaced.

• Tools missing, greyed out, or "not connected" - the server did not finish connecting. To fix it, re-open MCP Connections, reconnect reui, and authorize again, then restart v0.
• Tools are listed but nothing runs - v0 gates MCP tool calls behind a permission mode. Approve the call when v0 asks, or switch the mode from Ask to Auto.
• 401 and you signed in with OAuth - your ReUI session expired. To fix it, re-open MCP Connections, reconnect reui, and authorize again to sign in again.
• 401 and you used a personal token - the token expired or was revoked. Reconnecting will not help, since the connection sends the token you pasted rather than a browser session. Create a new token at Account → MCP and update the connection. The 401 body names which of the two it was.
• Requests hang or the session drops mid-build - long sessions can lose the connection. To fix it, re-open MCP Connections, reconnect reui, and authorize again and retry your last prompt.
• Sign-in appears to work but every call still 401s - check whether you pasted a token instead of connecting with OAuth. A pasted credential is sent on every request and takes precedence over an OAuth session, so if it is wrong or expired the calls keep failing. Fix it by reconnecting reui and authorizing in the browser, or by replacing the credential with a valid one. The two are alternatives, not layers.
• 429 "daily limit reached" - you hit the free limit of 100 tool calls per day. Sign in with your ReUI license for unlimited access, or wait for the next day.
• Every ReUI call fails and nothing asks you to sign in - the stored OAuth connection is dead (revoked, expired, or invalidated after a suspicious reuse), and the client is silently retrying a credential that can never work again. Account → MCP shows the connection as Disconnected when this is the case. Reconnect the same way as the 401 fix above; retrying without signing in again cannot recover it.