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Response Mapping

The Response tab lets you map fields from your API response to evaluation variables using JSONPath expressions.

Response Tab

Response Mapping Fields

Field Required Description Example JSONPath
actual_output Yes Main text response from the API choices[0].message.content
retrieval_context No Source chunks used for RAG metrics sources[*].content
tools_called No Tool/function calls for Agent metrics tool_calls[*].function.name
token_usage No Token count for cost calculation usage.total_tokens
system_prompt No System prompt used by the AI system_prompt

How It Works

  1. First, send a test request from the Connection tab
  2. The API response JSON appears in the bottom panel
  3. Click on values in the JSON tree to auto-fill the JSONPath
  4. Or manually type JSONPath expressions

OpenAI Response Mapping

For a standard OpenAI API response: 

{
  "choices": [{"message": {"content": "Hello!"}}],
  "usage": {"total_tokens": 150}
}
- actual_output: choices[0].message.content - token_usage: usage.total_tokens

Note

If no test response is available yet, the bottom panel shows "No test response yet. Send a test request in the Connection tab first."

JSONPath Syntax

Pattern Description
field.subfield Nested object access
array[0] First element of array
array[*].field All elements' field values (returns array)
choices[0].message.content Deeply nested access