Add External API Integrations

Give your agent the ability to take action. Tools let the LLM call external APIs, query databases, book appointments, and check order status — anything your webhook can handle. What you’ll learn: How to define tools with JSON Schema, configure webhooks, handle responses, and test tool execution.

Quick start: Add a tool

Navigate to Tools tab

When creating or editing an agent, select the Tools tab.

Add a new tool

Click Add Tool to create a new tool configuration.

Configure settings

Tool Name: Unique identifier (e.g., get_weather)
Description: What the tool does and when to use it
Schema: Define parameters using JSON Schema
Webhook URL: Your endpoint
Headers: Authentication and custom headers

Test your tool

Click Test Tool, enter sample arguments, and verify the response.

Save and enable

Save the agent and toggle Allow this agent to take calls.

How function calling works

When you configure tools, the LLM gains awareness of available functions and autonomously decides when to call them during conversation. Dasha BlackBox sends requests to your webhook, your webhook executes the function, and the LLM incorporates results into its response.Key capabilities: JSON Schema for tool definitions, call metadata (callId, agentId, orgId) in webhook requests, automatic retry with exponential backoff, and built-in testing.

Define a tool

Tool structure

{
  "name": "get_weather",
  "description": "Get current weather for a city",
  "schema": {
    "type": "object",
    "properties": {
      "city": {
        "type": "string",
        "description": "City name"
      },
      "units": {
        "type": "string",
        "enum": ["celsius", "fahrenheit"]
      }
    },
    "required": ["city"]
  },
  "webhook": {
    "url": "https://api.example.com/tools/weather",
    "headers": {
      "Authorization": "Bearer your-api-key"
    }
  },
  "fallBackResult": {
    "temperature": "unknown",
    "conditions": "unavailable"
  }
}

Required fields

Field	Type	Description
`name`	string	Unique identifier. Pattern: `^[a-zA-Z_][a-zA-Z0-9_]*$`. No hyphens.
`description`	string	Clear explanation of what the tool does. Helps LLM decide when to use it.
`schema`	object	JSON Schema defining parameters.
`webhook`	object	URL and headers for the endpoint.

Optional fields

Field	Type	Description
`fallBackResult`	any	Default result if webhook fails. Allows conversation to continue gracefully.
`timeoutSeconds`	integer	Max wait time (1–300). Note: Currently uses fixed 60s HTTP timeout.
`retryCount`	integer	Retry attempts (0–5). Uses global retry policy with exponential backoff.

JSON Schema examples

Simple parameters

{
  "name": "send_sms",
  "description": "Send an SMS message",
  "schema": {
    "type": "object",
    "properties": {
      "phone_number": {
        "type": "string",
        "pattern": "^\\+[1-9]\\d{1,14}$",
        "description": "Phone in E.164 format"
      },
      "message": {
        "type": "string",
        "maxLength": 160,
        "description": "Message content"
      }
    },
    "required": ["phone_number", "message"]
  }
}

Nested objects

{
  "name": "book_appointment",
  "description": "Schedule an appointment",
  "schema": {
    "type": "object",
    "properties": {
      "customer": {
        "type": "object",
        "properties": {
          "name": { "type": "string" },
          "email": { "type": "string", "format": "email" },
          "phone": { "type": "string" }
        },
        "required": ["name", "email"]
      },
      "appointment": {
        "type": "object",
        "properties": {
          "datetime": { "type": "string", "format": "date-time" },
          "duration_minutes": { "type": "integer", "minimum": 15 },
          "service_type": {
            "type": "string",
            "enum": ["consultation", "follow-up", "emergency"]
          }
        },
        "required": ["datetime", "service_type"]
      }
    },
    "required": ["customer", "appointment"]
  }
}

Arrays

{
  "name": "search_products",
  "description": "Search product catalog",
  "schema": {
    "type": "object",
    "properties": {
      "keywords": {
        "type": "array",
        "items": { "type": "string" },
        "minItems": 1
      },
      "categories": {
        "type": "array",
        "items": {
          "type": "string",
          "enum": ["electronics", "clothing", "home", "books"]
        }
      },
      "in_stock_only": {
        "type": "boolean",
        "default": true
      }
    },
    "required": ["keywords"]
  }
}

Enumerations

{
  "name": "update_ticket_status",
  "description": "Update support ticket status",
  "schema": {
    "type": "object",
    "properties": {
      "ticket_id": {
        "type": "string",
        "pattern": "^TKT-[0-9]{6}$"
      },
      "status": {
        "type": "string",
        "enum": ["open", "in_progress", "waiting_customer", "resolved", "closed"]
      },
      "priority": {
        "type": "string",
        "enum": ["low", "medium", "high", "urgent"]
      }
    },
    "required": ["ticket_id", "status"]
  }
}

Configure webhooks

Request format

When your tool is invoked, Dasha BlackBox sends a POST request:

POST https://api.example.com/webhooks/tools
Content-Type: application/json
Authorization: Bearer sk-abc123...

{
  "type": "ToolWebHookPayload",
  "status": "Running",
  "callId": "67890abcdef123456789",
  "agentId": "12345abcdef67890",
  "orgId": "org_abc123xyz",
  "toolName": "get_weather",
  "arguments": {
    "city": "San Francisco",
    "units": "fahrenheit"
  },
  "callAdditionalData": {
    "campaign_id": "summer_outreach"
  },
  "agentAdditionalData": {
    "department": "sales"
  }
}

Only headers configured in your tool definition are sent. The callAdditionalData, agentAdditionalData, serverJobId, and sip fields are optional.

Response format

Return a JSON response within the timeout period:Success (200 OK):

{
  "temperature": 68,
  "conditions": "sunny",
  "humidity": 65
}

Error Response (4xx/5xx)

{
  "error": "Invalid city name",
  "errorCode": "INVALID_CITY"
}

If your webhook returns an error, the fallBackResult is used (if configured).

Response best practices

Return structured data with clear field names
Include context for the LLM to formulate complete responses
Handle errors gracefully — return error objects instead of crashing
Be concise — avoid massive datasets, summarize when possible
Respond quickly — aim for sub-second responses

Test webhooks

Via dashboard

Navigate to agent’s Tools tab
Click Test Tool on any configured tool
Enter sample arguments
Review request/response in real-time

Via API

const response = await fetch('https://blackbox.dasha.ai/api/v1/webhooks/test', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    webHook: {
      url: 'https://api.example.com/webhooks/tools',
      headers: {
        'Authorization': 'Bearer your-webhook-key'
      }
    },
    webhookType: 'ToolWebHookPayload',
    toolName: 'get_weather',
    toolArguments: {
      city: 'San Francisco',
      units: 'fahrenheit'
    }
  })
});

const result = await response.json();
console.log(result);
// Output:
// {
//   "success": true,
//   "httpStatus": 200,
//   "httpStatusText": "OK",
//   "responseData": { "temperature": 68, "conditions": "sunny" },
//   "validationResult": { "isValid": true, "errors": [] },
//   "timeTaken": 145
// }

Tool webhooks vs event webhooks

Feature	Tool webhooks	Event webhooks
Purpose	Execute functions during conversation	Receive call lifecycle notifications
Trigger	LLM decides to invoke a tool	Specific events (call start, result, failure)
Response	Returns result to LLM	Acknowledgment only
Timeout	60 seconds	30 seconds
Configure in	Tools tab	Webhooks tab

See Webhook Events for event webhook details.

MCP tools

Dasha BlackBox integrates with Model Context Protocol (MCP) servers for pre-built tools without custom webhook development.

MCP vs custom webhooks

Feature	Custom webhooks	MCP servers
Setup	Write webhook handler	Connect to existing server
Tool discovery	Manual definition	Automatic from server
Hosting	Self-hosted or cloud	MCP server provider
Customization	Full control	Limited to server capabilities

Use custom webhooks for full control or proprietary system integration. Use MCP connections for standard integrations like databases, calendars, or public APIs. See MCP Connections for setup instructions.

Common use cases

CRM integration

{
  "name": "lookup_customer",
  "description": "Retrieve customer information by email or phone",
  "schema": {
    "type": "object",
    "properties": {
      "identifier": {
        "type": "string",
        "description": "Customer email or phone number"
      }
    },
    "required": ["identifier"]
  },
  "webhook": {
    "url": "https://crm.example.com/api/webhooks/lookup",
    "headers": {
      "Authorization": "Bearer crm-api-key"
    }
  }
}

Calendar booking

{
  "name": "check_availability",
  "description": "Check available appointment slots",
  "schema": {
    "type": "object",
    "properties": {
      "start_date": {
        "type": "string",
        "format": "date",
        "description": "Start date (YYYY-MM-DD)"
      },
      "end_date": {
        "type": "string",
        "format": "date",
        "description": "End date (YYYY-MM-DD)"
      },
      "service_type": {
        "type": "string",
        "description": "Type of service"
      }
    },
    "required": ["start_date", "end_date"]
  }
}

Knowledge base search

{
  "name": "search_knowledge_base",
  "description": "Search company knowledge base",
  "schema": {
    "type": "object",
    "properties": {
      "query": {
        "type": "string",
        "description": "Search query"
      },
      "category": {
        "type": "string",
        "enum": ["products", "policies", "troubleshooting"]
      },
      "max_results": {
        "type": "integer",
        "minimum": 1,
        "maximum": 10,
        "default": 5
      }
    },
    "required": ["query"]
  }
}

Best practices

Tool design

Keep tools focused — one tool, one purpose
Write clear descriptions — explain when the LLM should use the tool
Use strong typing — precise schemas with proper types, enums, formats
Provide defaults — sensible fallback results for error handling

Schema guidelines

// ✅ Good: Descriptive with constraints
{
  "customer_email": {
    "type": "string",
    "format": "email",
    "description": "Customer's email for order confirmation"
  }
}

// ❌ Avoid: Vague and unconstrained
{
  "email": {
    "type": "string",
    "description": "Email"
  }
}

Webhook implementation

Security:

Always use HTTPS endpoints
Implement authentication via headers
Validate incoming requests
Rate limit to prevent abuse

Performance:

Respond within timeout (aim for < 1 second)
Use async processing for slow operations
Implement caching where appropriate

Reliability:

Use idempotent operations when possible
Monitor webhook uptime
Set up alerting for failures

Troubleshooting

Tool not being called

Improve the tool description to be more specific
Mention the tool in system prompt if critical
Test with explicit user requests that should trigger the tool
Check that the tool name is clear and descriptive

Webhook timeouts

Optimize webhook processing time
Use async processing and return immediately
Configure appropriate fallBackResult

Schema validation errors

Review LLM-generated arguments in call logs
Simplify complex nested schemas
Add clear descriptions to all properties
Use enums to constrain values

Authentication failures

Verify header configuration in tool setup
Check that API keys are valid and not expired
Ensure webhook URL is correct and accessible
Test webhook independently with curl/Postman

Next steps

MCP connections

Connect to MCP servers for pre-built tools

Webhook events

Configure call lifecycle notifications

Test webhooks

Validate webhook implementations

Dashboard testing

Test tools in real conversations

Introduction

Create

Test

Deploy

Monitor

Advanced Features

Troubleshooting

Quick start: Add a tool

Define a tool

Required fields

Optional fields

JSON Schema examples

Configure webhooks

Response best practices

Test webhooks

Via dashboard

Tool webhooks vs event webhooks

MCP tools

MCP vs custom webhooks

Common use cases

Best practices

Tool design

Webhook implementation

Troubleshooting

Next steps

MCP connections

Webhook events

Test webhooks

Dashboard testing

​Quick start: Add a tool

​Define a tool

​Required fields

​Optional fields

​JSON Schema examples

​Configure webhooks

​Response best practices

​Test webhooks

​Via dashboard

​Tool webhooks vs event webhooks

​MCP tools

​MCP vs custom webhooks

​Common use cases

​Best practices

​Tool design

​Webhook implementation

​Troubleshooting

​Next steps

MCP connections

Webhook events

Test webhooks

Dashboard testing

Quick start: Add a tool

Define a tool

Required fields

Optional fields

JSON Schema examples

Configure webhooks

Response best practices

Test webhooks

Via dashboard

Tool webhooks vs event webhooks

MCP tools

MCP vs custom webhooks

Common use cases

Best practices

Tool design

Webhook implementation

Troubleshooting

Next steps