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ToolAI Tools & APIsv2.0

OpenAI Function Calling

by OpenAI · paid · Last verified 2026-03-17

OpenAI's native capability for models to generate structured function calls in API responses. Enables reliable tool use by having models output JSON arguments matching defined function schemas.

https://platform.openai.com/docs/guides/function-calling
B+
B+Good
Adoption: A+Quality: AFreshness: A+Citations: AEngagement: F

Specifications

License
Proprietary
Pricing
paid
Capabilities
function-calling, structured-output, tool-use, parallel-calls, strict-mode
Integrations
langchain, llamaindex, litellm
Use Cases
tool-use, api-integration, data-extraction, agent-actions
API Available
Yes
SDK Languages
python, typescript
Deployment
cloud
Rate Limits
Part of OpenAI API rate limits
Data Privacy
OpenAI API data processing terms apply
Tags
function-calling, openai, tool-use, structured-output
Added
2026-03-17
Completeness
100%

Index Score

74.8
Adoption
90
Quality
88
Freshness
90
Citations
85
Engagement
0

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