# MCP tool reference

1 callable tools.

Use tools/call at https://mcp.schedulerzero.com/mcp with the exact tool name and arguments below. The /tools/ paths in this view are documentation identifiers, not HTTP endpoints. Request execution is disabled for this reference.

Inputs are shown for personal API keys (bound) and for OAuth/delegated agents. Output schemas describe MCP structuredContent: native objects pass through; arrays, scalars and null use a data wrapper. Text content retains the native JSON result.

[Connect a client](/mcp/connect) · [Authentication and authorization](/authentication) · [Generated auth guide](/auth.md) · [Download tool catalog](/mcp-catalog.json) · [Agent documentation](/llms.txt)

## assign_leads

Assign a campaign contact to a workspace member (action=assign) or remove the assignment (action=remove).

Use to route a campaign contact; assign requires a current member, remove deliberately does not.

Removal is idempotent and never fails for stale assignments — do not pre-check membership.

Obtain the user's explicit authorization before invoking a write or destructive action. This is a client interaction requirement, not a server-issued approval token.

Scopes: lead:update

Risk: write; confirmation: explicit; idempotency: supported.

### Input schema (personal API key)

```json
{
  "type": "object",
  "properties": {
    "workspaceId": {
      "type": "string",
      "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$",
      "format": "uuid"
    },
    "action": {
      "type": "string",
      "enum": [
        "assign",
        "remove"
      ]
    },
    "campaignContactId": {
      "type": "string",
      "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$",
      "format": "uuid"
    },
    "assigneeUserId": {
      "type": "string",
      "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$",
      "format": "uuid"
    }
  },
  "required": [
    "workspaceId",
    "action",
    "campaignContactId",
    "assigneeUserId"
  ],
  "patternProperties": {
    "^(?!(?:workspaceId|action|campaignContactId|assigneeUserId)$)[\\s\\S]*$": false
  },
  "additionalProperties": true,
  "propertyNames": {
    "type": "string",
    "enum": [
      "workspaceId",
      "action",
      "campaignContactId",
      "assigneeUserId"
    ]
  }
}
```

### Input schema (OAuth / delegated agent)

```json
{
  "type": "object",
  "properties": {
    "workspaceId": {
      "type": "string",
      "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$",
      "format": "uuid"
    },
    "action": {
      "type": "string",
      "enum": [
        "assign",
        "remove"
      ]
    },
    "campaignContactId": {
      "type": "string",
      "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$",
      "format": "uuid"
    },
    "assigneeUserId": {
      "type": "string",
      "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$",
      "format": "uuid"
    }
  },
  "required": [
    "workspaceId",
    "action",
    "campaignContactId",
    "assigneeUserId"
  ],
  "patternProperties": {
    "^(?!(?:workspaceId|action|campaignContactId|assigneeUserId)$)[\\s\\S]*$": false
  },
  "additionalProperties": true,
  "propertyNames": {
    "type": "string",
    "enum": [
      "workspaceId",
      "action",
      "campaignContactId",
      "assigneeUserId"
    ]
  }
}
```

### Output schema (structuredContent)

```json
{
  "type": "object",
  "properties": {
    "success": {
      "anyOf": [
        {
          "type": "boolean",
          "enum": [
            true
          ]
        }
      ]
    }
  },
  "required": [
    "success"
  ],
  "patternProperties": {
    "^(?!(?:success)$)[\\s\\S]*$": false
  },
  "additionalProperties": true,
  "propertyNames": {
    "anyOf": [
      {
        "type": "string",
        "enum": [
          "success"
        ]
      }
    ]
  }
}
```

### Underlying API operations

- `campaignContactAssignments.create`: `POST /v1/workspaces/:workspaceId/leads/:campaignContactId/assignees`
- `campaignContactAssignments.remove`: `DELETE /v1/workspaces/:workspaceId/leads/:campaignContactId/assignees/:assigneeUserId`