OpenAI API · sdk · fg-0145

zodTextFormat with Zod 4 fails: schema must be a JSON Schema of type object, got type string

Invalid schema for response_format: schema must be a JSON Schema of 'type: "object"', got 'type: "string"'.

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

Before 6.7.0 the SDK converted schemas with a library that only understood Zod 3, so Zod 4 objects turned into a wrong schema.

Fix

Upgrade openai to 6.7.0 or later, or pin zod to version 3.

Apply

npm install openai@^6.7.0

Affects: openai-node earlier than 6.7.0 with zod 4; fixed in 6.7.0, 2025-10-24

Sources

• https://github.com/openai/openai-node/issues/1602
• https://github.com/openai/openai-node/issues/1576

claude mcp add --transport http footgun https://getfootgun.com/api/mcp