AI Development
Strict Mode (Tool Schemas)
A flag, strict: true, set on a tool or function definition that makes the model's tool arguments always conform to the declared JSON Schema instead of following it on a best-effort basis.
In depth
A flag, strict: true, set on a tool or function definition that makes the model's tool arguments always conform to the declared JSON Schema instead of following it on a best-effort basis. It works through constrained decoding, so malformed or missing arguments are not sampled in the first place. OpenAI requires additionalProperties to be false on every object and every property to be listed as required when strict is on, and Anthropic offers the same guarantee for Claude as strict tool use. OpenAI recommends always enabling it.
Primary source: developers.openai.com
Example
In practice, developers reach for Strict Mode (Tool Schemas) when they need the capability described above as part of an AI feature or workflow.
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FAQ
Common questions
What is Strict Mode (Tool Schemas)?
A flag, strict: true, set on a tool or function definition that makes the model's tool arguments always conform to the declared JSON Schema instead of following it on a best-effort basis.
Why does Strict Mode (Tool Schemas) matter for AI developers?
Strict Mode (Tool Schemas) sits in the AI Development part of the AI stack. Understanding it helps you make better decisions when building, debugging, and shipping AI features.
Where can I learn more about Strict Mode (Tool Schemas)?
Developers Digest publishes tutorials and videos that cover AI Development topics including Strict Mode (Tool Schemas). Check the blog and YouTube channel for hands-on walkthroughs.
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