openFDA Recall API Has Silent Data Traps Developers Must Know

The openFDA enforcement API offers free access to U.S. recall data across drug, device, and food categories, but contains several undocumented failure modes that return HTTP 200 responses with incorrect results. The API has four distinct recall endpoints that are not interchangeable — three share a common schema while device/recall.json uses an entirely different structure and refreshes on a separate schedule. A critical query bug causes unparenthesized OR operators to silently discard all but the last search clause, returning wrong record counts without raising any error. Developers must also avoid using generic URL encoders on query strings, as percent-encoding the plus sign breaks range queries and triggers unhelpful HTTP 500 errors. Additional hard limits include a maximum of 1,000 results per request and a skip-based pagination cap of 25,000 records, requiring careful handling for full dataset retrieval.