Support JSON schema for Gemini 2.5

[namuorg]

Description

One of the limitations of using structured outputs with Gemini is that it uses a subset of the OpenAPI 3.0 spec rather than JSON Schema:

• https://ai-sdk.dev/providers/ai-sdk-providers/google-generative-ai#schema-limitations
• Invalid JSON payload received (Google Provider). #2743

This prevents enabling structured outputs when using Zod unions and records.

However, Gemini 2.5 models now support JSON Schema as a preview: https://ai.google.dev/gemini-api/docs/structured-output#json-schema

I would love for the AI SDK to support submitting JSON Schema to Gemini 2.5 models as it would allow enabling structured outputs for higher quality output that follows the schema.

[theo-m]

Passing by, I think this package is relevant (at least it helped me keep my json schemas when interacting with older Gemini models)
https://www.npmjs.com/package/@openapi-contrib/json-schema-to-openapi-schema

[andresilva-cc]

Passing by, I think this package is relevant (at least it helped me keep my json schemas when interacting with older Gemini models) https://www.npmjs.com/package/@openapi-contrib/json-schema-to-openapi-schema

Did you use it in conjunction with one of the ai helpers? I'm trying to reuse a complex Zod v3 schema but nothing seems to work, Gemini won't accept it.

[nogueira-gg]

Any updates on this?

[lgrammel]

Identify issue type

Identified type: Feature
Confidence: High

Rationale: This is a request to add provider capability/support for JSON Schema with Gemini 2.5 structured outputs, which is an enhancement rather than a bug or documentation change.

Evidence:

• The issue states Gemini 2.5 models now support JSON Schema as a preview and asks for AI SDK to support submitting JSON Schema to Gemini 2.5 models.
• The request is framed as enabling a new capability for structured outputs with Gemini, not as a broken existing behavior.
• Comments discuss possible workarounds and ask for updates, without adding a concrete current SDK failure.