Structured outputs on the Claude Developer Platform
Guarantee responses match your JSON schemas and tool definitions with structured outputs.

NBIM、Brex などのチームが Claude on AWS Bedrock を使って信頼できる AI エージェントを構築する方法をご覧ください。
NBIM、Brex などのチームが Claude on AWS Bedrock を使って信頼できる AI エージェントを構築する方法をご覧ください。
NBIM、Brex などのチームが Claude on AWS Bedrock を使って信頼できる AI エージェントを構築する方法をご覧ください。
Guarantee responses match your JSON schemas and tool definitions with structured outputs.
The Claude Developer Platform now supports structured outputs for Claude Sonnet 4.5 and Opus 4.1. Available in public beta, this feature ensures API responses always match your specified JSON schemas or tool definitions.
With structured outputs, developers can eliminate schema-related parsing errors and failed tool calls by ensuring that Claude's responses conform to a defined schema—whether you're extracting data from images, orchestrating agents, or integrating with external APIs.
For developers building applications and agents in production, a single error in data formatting can cause cascading failures. Structured outputs solves this by guaranteeing your response matches the exact structure you define, without any impact to model performance. This makes Claude dependable for applications and agents where accuracy is critical, including:
Structured outputs can be used two ways: with JSON or tools. When used with JSON, you provide your schema definition in the API request. For tools, you define your tool specifications, and Claude's output conforms to those tool definitions automatically.
The end result is a reliable output, reduced retries, and a simplified codebase that no longer needs failover logic or complex error handling.
OpenRouter provides 4M+ developers access to all major AI models through a single, unified interface.
"Structured outputs have become a really valuable part of the agentic AI stack. Agents constantly ingest and produce structured data, so Anthropic’s structured outputs close a real gap for developers. Agent workflows run reliably, every time, and teams can focus on their customers rather than debugging tool calls,” said Chris Clark, COO, OpenRouter.
Structured outputs is now available in public beta for Sonnet 4.5 and Opus 4.1 on the Claude Developer Platform, with support for Haiku 4.5 coming soon. Explore our documentation for supported JSON schema types, implementation examples, and best practices.
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