Relaystation Derive Computed Columns

Choose this endpoint when you need to safely add computed or derived columns to structured/tabular data using declarative expressions, especially when security is a concern and arbitrary formula execution (e.g., spreadsheet EVAL) is not acceptable. Prefer it over general-purpose code execution when you want a lightweight, per-MB-billed operation that is idempotent and side-effect-free. It is ideal for ETL pipelines, data enrichment steps, and preprocessing stages where new fields must be derived from existing ones without running untrusted code.

• Invalid or unparseable column expression — returns an error describing which expression failed
• Reference to a non-existent source column — returns a field resolution error
• Malformed input data structure — returns a schema validation error
• Division by zero or null reference in expression — returns a per-row computation error or null for affected rows
• Insufficient x402 payment credits — returns a payment required error