data structure

When you connect blocks, the output data structure from the source block determines what values are available in the destination block. Each block type produces a specific output structure that you can reference in downstream blocks.

Understanding these data structures is essential for effectively using connection tags and accessing the right data in your workflows.

Block Output Structures

Different block types produce different output structures. Here's what you can expect from each block type:

{
  "content": "The generated text response",
  "model": "gpt-4o",
  "tokens": {
    "prompt": 120,
    "completion": 85,
    "total": 205
  },
  "toolCalls": [...],
  "cost": [...],
  "usage": [...]
}

Agent Block Output Fields

content: The main text response generated by the agent
model: The AI model used (e.g., "gpt-4o", "claude-3-opus")
tokens: Token usage statistics
- prompt: Number of tokens in the prompt
- completion: Number of tokens in the completion
- total: Total tokens used
toolCalls: Array of tool calls made by the agent (if any)
cost: Array of cost objects for each tool call (if any)
usage: Token usage statistics for the entire response

{
  "data": "Response data",
  "status": 200,
  "headers": {
    "content-type": "application/json",
    "cache-control": "no-cache"
  }
}

API Block Output Fields

data: The response data from the API (can be any type)
status: HTTP status code of the response
headers: HTTP headers returned by the API

{
  "result": "Function return value",
  "stdout": "Console output",
}

Function Block Output Fields

result: The return value of the function (can be any type)
stdout: Console output captured during function execution

{
  "content": "Evaluation summary",
  "model": "gpt-5",
  "tokens": {
    "prompt": 120,
    "completion": 85,
    "total": 205
  },
  "metric1": 8.5,
  "metric2": 7.2,
  "metric3": 9.0
}

Evaluator Block Output Fields

content: Summary of the evaluation
model: The AI model used for evaluation
tokens: Token usage statistics
[metricName]: Score for each metric defined in the evaluator (dynamic fields)

{
  "content": "Original content passed through",
  "conditionResult": true,
  "selectedPath": {
    "blockId": "2acd9007-27e8-4510-a487-73d3b825e7c1",
    "blockType": "agent",
    "blockTitle": "Follow-up Agent"
  },
  "selectedConditionId": "condition-1"
}

Condition Block Output Fields

content: The original content passed through
conditionResult: Boolean result of the condition evaluation
selectedPath: Information about the selected path
- blockId: ID of the next block in the selected path
- blockType: Type of the next block
- blockTitle: Title of the next block
selectedConditionId: ID of the selected condition

{
  "content": "Routing decision",
  "model": "gpt-4o",
  "tokens": {
    "prompt": 120,
    "completion": 85,
    "total": 205
  },
  "selectedPath": {
    "blockId": "2acd9007-27e8-4510-a487-73d3b825e7c1",
    "blockType": "agent",
    "blockTitle": "Customer Service Agent"
  }
}

Router Block Output Fields

content: The routing decision text
model: The AI model used for routing
tokens: Token usage statistics
selectedPath: Information about the selected path
- blockId: ID of the selected destination block
- blockType: Type of the selected block
- blockTitle: Title of the selected block

Custom Output Structures

Some blocks may produce custom output structures based on their configuration:

Agent Blocks with Response Format: When using a response format in an Agent block, the output structure will match the defined schema instead of the standard structure.
Function Blocks: The result field can contain any data structure returned by your function code.
API Blocks: The data field will contain whatever the API returns, which could be any valid JSON structure.

Always check the actual output structure of your blocks during development to ensure you're referencing the correct fields in your connections.

Nested Data Structures

Many block outputs contain nested data structures. You can access these using dot notation in connection tags:

<blockId.path.to.nested.data>

For example:

<agent1.tokens.total> - Access the total tokens from an Agent block
<api1.data.results[0].id> - Access the ID of the first result from an API response
<function1.result.calculations.total> - Access a nested field in a Function block's result

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