RecipesCustom plugin install

Why custom plugins matter

Custom MCP plugins let your team ground Mesrai on internal systems—knowledge bases, incident dashboards, policy engines, you name it. Once installed, every Mesrai interaction can call those tools with live data, so reviewers stop copying screenshots or stale snippets into pull requests.

This guide shows the opinionated flow we recommend for any custom plugin, whether it is a simple read-only endpoint (like the Mesrai Docs MCP) or a more advanced pipeline with authentication.

Mesrai supports remote MCP servers only—that means the plugin must be reachable from Mesrai’ infrastructure.

Prepare your plugin info

Gather these details before opening the Plugins catalog:

FieldWhy it matters
Public URLEndpoint where the MCP manifest is hosted (e.g., https://acme-internal-tools.com/mcp).
ProtocolMCP implementation type (HTTP or SSE).
HostingMust be a remote server accessible from Mesrai (no localhost or desktop MCP endpoints).
AuthenticationWhether the plugin requires API keys, OAuth, or is open to your workspace IPs.
Description / LogoHelps other engineers understand what the plugin does when browsing the catalog.

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  • Smithery.ai curates deployable MCP services plus an easy launcher you can point at your own infra.
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Install the plugin in Mesrai

  1. Go to Code Review Settings → Plugins (beta) inside your Mesrai workspace.

  2. Click Add Plugin.

  3. Fill in the form:

    Plugin Name: Descriptive label (e.g., "Security Runbooks MCP")
Description: What data/actions it exposes
Logo URL: Optional, but helpful for recognition
URL: https://your-domain.com/mcp
Protocol: HTTP or SSE
Authorization / Headers: Add if your MCP host requires them (e.g., API key, OAuth, etc.) (optional)

  4. Hit Create Plugin. Once it appears in the list, it is instantly available to the entire workspace.

Custom plugins run with the same permissions as the workspace. Only install endpoints your organization trusts and monitors.

Verify the connection

  1. Open any pull request where Mesrai is enabled.

  2. Mention @mesrai and include a question that forces the plugin to respond.

    @mesrai can you fetch the deployment checklist from our MCP and confirm whether feature flags are required?

  3. In the drawer, check the Plugins section. You should see a call to your new plugin. If it fails, expand the error to inspect the status code or validation message.

The Mesrai Docs MCP (https://docs.mesrai.com/mcp) is a quick sanity test—you can install it first to ensure your workspace can reach external hosts.

Quick checklist

  • Plugin manifest is hosted and reachable.
  • Auth model (if any) is documented and tested.
  • Plugin is installed via Add Custom Plugin with the right URL + headers.
  • A sample PR proved Mesrai can call the plugin.
  • Owners know how to monitor and update the integration.
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