describe_fields

Inspect one source's effective fields for safe exact matching, grouping or sorting.

Requires a configured schema backend; missing configuration fails clearly, not by guessing. When direct schema endpoints are unavailable, fields are inferred from sample hits through the configured search backend.

Input:

{
  "source_id": "workflow_metrics",
  "query": "event",
  "limit": 50
}

Output includes:

• field name
• field type
• searchable
• aggregatable
• available subfields
• preferred_exact_field when a safer exact-match variant exists, such as .keyword