OpenAI-Compatible Is Becoming a Fiction We Keep Paying For — The Production Edges That Break in…

OpenAI-Compatible Is Becoming a Fiction We Keep Paying For - The Production Edges That Break in 2026 I’ve watched “OpenAI-compatible” stop meaning portable the moment a workflow needed structured output, file handling, or tool calls that weren’t on the happy path. As of 2026-03-10, my working definition is blunt: most vendors mean wire compatibility, not behavior compatibility. The request shape often looks close enough that the OpenAI SDK connects. The trouble starts one layer up - schema-enforced outputs, file inputs, streaming event semantics, reasoning fields, and tool-call replay.