> ## Documentation Index
> Fetch the complete documentation index at: https://docs.budecosystem.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Connector Concepts

> Core concepts behind Bud connectors, connections, gateways, tools, and triggers

## Connector

A connector is a catalog entry or custom definition that describes an external system Bud can connect to. Registry connectors include metadata such as name, provider, category, documentation URL, authentication type, and credential schema.

## Gateway

A gateway is a configured MCP connection created from a registry connector or custom MCP server. Gateways store connection metadata, tags, enabled state, authorization status, and available tools.

```mermaid theme={null}
flowchart TD
  A[Registry Connector] -->|configure credentials| B[Gateway]
  C[Custom MCP Server] -->|create custom gateway| B
  B --> D[OAuth Status]
  B --> E[Tool List]
  B --> F[Visibility Tags]
  E --> G[Agent Prompt Config]
```

## Tool

A tool is an MCP operation exposed by a gateway. Agents do not automatically receive every tool from a connection; users select the exact tool IDs to attach.

## OAuth Status

OAuth-capable gateways have an authorization status. Bud starts OAuth with the gateway ID, stores return context during the redirect, and completes the callback with the provider authorization code and state.

## Visibility Scope

Connector visibility controls where a configured connection can be used.

| Scope        | Behavior                                               | Best For                                                   |
| ------------ | ------------------------------------------------------ | ---------------------------------------------------------- |
| **Global**   | Agents in all projects can discover the connection.    | Organization-wide systems and shared internal tools.       |
| **Project**  | Only selected project IDs can discover the connection. | Team-specific systems, restricted data, or staged rollout. |
| **Disabled** | The connection exists but is not available to agents.  | Maintenance, incident response, or temporary suspension.   |

## Event Connection

An event connection is a shared provider-level source for triggers. Event connections use descriptor-driven credentials, can be project-scoped or global, and may expose a webhook URL after provisioning.

## Trigger Provider Descriptor

Provider descriptors define event credentials, provider metadata, sample payloads, and grouping suggestions. Bud Admin uses descriptors to render the credentials step and trigger grouping experience without hardcoding provider-specific fields.

## Prompt Attachment

Attaching a connection to an agent stores selected MCP tool IDs in the prompt configuration. Detaching removes the gateway link from that agent only; it does not delete the shared gateway.

<Warning>
  Deleting a configured gateway is different from detaching it from an agent. Delete removes the shared connection; detach only updates one agent's prompt configuration.
</Warning>