Connector Configuration

The connectors array lives in workspace.json, not nimblebrain.json — where the name connectors belongs to the provider and gateway block instead. Each workspace declares its own connectors. This page documents the shape of a single entry — the same shape whether it was written by hand, by the connectors install flow, or by the CLI.

Every entry is one remote MCP server, addressed by URL. The runtime orchestrates over remote MCP: it connects to a URL with a credential, and does not download, verify, or execute a server’s code. There is no by-name or by-path entry, and nothing runs as a subprocess of the platform.

NimbleBrain ships with no connectors by default. Platform capabilities (conversations, files, usage, tasks) are built in as in-process tool sources — install connectors to give a workspace domain-specific tools.

Note

Connectors are workspace-scoped. Two workspaces that install the same server hold independent credentials and independent connection state. See workspace.json for where the array lives and how workspaces are managed.

The entry shape

{
  "connectors": [
    {
      "url": "https://mcp.example.com/mcp",
      "serverName": "example",
      "transport": {
        "type": "streamable-http",
        "auth": { "type": "bearer", "token": "sk-..." }
      }
    }
  ]
}

Field	Type	Default	Description
url	string	—	Required. The remote MCP endpoint.
serverName	string	—	Required. The name the server registers under. Tools reach the agent as <serverName>__<tool>, so this is the stable identity every other surface looks the connector up by. Set automatically at install from the catalog entry’s canonical id.
transport	object	{ "type": "streamable-http" }	How to reach the server. See Remote transport configuration.
ui	object | null	null	Host UI metadata, copied from the operator-trusted catalog entry at install. At every boot the runtime takes it from the catalog again, so a placement the catalog gains reaches connectors already installed; a connector no catalog entry names keeps this copy.
oauthScope	"workspace"	"workspace"	Identity scope for the connection. One identity per (workspace, server), shared by the workspace’s members.
scopes	string[]	—	OAuth scopes to request. Omit for servers that derive their own (DCR).
oauthClient	object	—	Pre-registered OAuth client for vendors without Dynamic Client Registration. clientSecret is a reference into the credential store, never an inline value — see Credentials.
additionalAuthorizationParams	object	—	Extra query params for the authorize URL (e.g. Google’s access_type=offline). Reserved OAuth keys are rejected at config load.

Tip

Don’t hand-write an auth.token for a service the catalog can connect over OAuth — install it from Browse instead, and the tokens land in the workspace credential store rather than in workspace.json. Inline static auth is for a server you operate yourself.

UI metadata

The ui field is populated automatically when you install a connector whose catalog entry declares UI metadata. You do not need to set this manually.

{
  "ui": {
    "placements": [
      { "slot": "main", "resourceUri": "ui://tasks/index.html" }
    ]
  }
}

Field	Type	Description
ui.placements	array	Placement declarations (each a slot plus a ui:// resource URI) that register the app’s views. Re-validated at every registration, so a malformed one is dropped rather than rendered.

Remote transport configuration

The transport object controls how NimbleBrain connects to the server.

{
  "url": "https://mcp.example.com/mcp",
  "serverName": "example",
  "transport": {
    "type": "streamable-http",
    "auth": { "type": "bearer", "token": "sk-..." },
    "headers": {
      "X-Custom-Header": "value"
    },
    "reconnection": {
      "maxRetries": 5,
      "initialReconnectionDelay": 1000,
      "maxReconnectionDelay": 30000
    },
    "sessionId": "resume-session-abc123"
  }
}

Transport fields

Field	Type	Default	Description
type	"streamable-http" | "sse"	"streamable-http"	Transport protocol. Streamable HTTP is the default MCP transport. Use "sse" for servers that only support Server-Sent Events.
auth	object	—	Authentication method. See auth types. Omit it for a server that signs in with OAuth: the connector waits for Connect.
headers	object	{}	Custom HTTP headers sent with every request. Keys and values are strings. Headers are sent to the connector’s origin only, never to an OAuth authorization server on another origin.
reconnection	object	—	Reconnection behavior. See reconnection.
sessionId	string	—	MCP session ID for resuming an existing session.

Auth types

Bearer token

{
  "auth": {
    "type": "bearer",
    "token": "sk-your-api-key"
  }
}

Sends an Authorization: Bearer <token> header with every request.

Custom header

{
  "auth": {
    "type": "header",
    "name": "X-API-Key",
    "value": "your-api-key"
  }
}

Sends a custom header with every request. Use this for APIs that expect a non-standard auth header.

No auth

{
  "auth": {
    "type": "none"
  }
}

No authentication headers are sent, and the connector starts without a Connect step. Use this for servers on a private network or behind a VPN. A server that signs in with OAuth omits auth instead.

Reconnection

Control how NimbleBrain handles dropped connections to remote servers.

Field	Type	Description
maxRetries	number	Maximum number of reconnection attempts before giving up.
initialReconnectionDelay	number	Milliseconds to wait before the first retry.
maxReconnectionDelay	number	Maximum milliseconds between retries (backs off exponentially up to this cap).

Complete example

{
  "id": "ws_00622b820b0ec363",
  "name": "Product",
  "connectors": [
    {
      "url": "https://mcp.example.com/mcp",
      "serverName": "example-remote",
      "transport": {
        "type": "streamable-http",
        "auth": { "type": "bearer", "token": "sk-..." },
        "headers": { "X-Tenant": "acme" },
        "reconnection": {
          "maxRetries": 3,
          "initialReconnectionDelay": 1000,
          "maxReconnectionDelay": 10000
        }
      }
    },
    {
      "url": "https://mcp.granola.ai/mcp",
      "serverName": "ai-granola-mcp",
      "oauthScope": "workspace"
    }
  ]
}