Function calling guide
Listed inFunction CallingAPIs & SDKson
OpenAI's reference on declaring tools, handling the model's call, strict schemas, and parallel tool use.
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OpenAI · developers.openai.com#api
#tools
The wire protocols and client libraries you'll actually write code against.
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7 articles
Listed inFunction CallingAPIs & SDKson
OpenAI's reference on declaring tools, handling the model's call, strict schemas, and parallel tool use.
Listed inFunction CallingAPIs & SDKson
The model returns a request your code chooses to run. Arguments are model-generated, and providers document the model inventing ones nobody supplied.
Listed inGoogle Gemini APIAPIs & SDKson
Four safety categories, five thresholds, and a default of OFF. Blocking arrives in a field rather than an exception.
Listed inClaude Messages APIAPIs & SDKson
The three required parameters include max_tokens, which is optional almost everywhere else. Content comes back as an array of typed blocks, so indexing the first one breaks the day you enable tools.
Listed inOpenAI-Compatible APIsAPIs & SDKson
Why half the ecosystem speaks one schema, and what breaks when you swap providers.
Listed inOpenAI Responses APIAPIs & SDKson
The successor to chat completions, with built-in tools and server-side state.
Listed inUsing SDKs DirectlyAPIs & SDKson
Skipping the framework and calling the provider client — usually the right first move.