Free LLM API for Function Calling

Keyword: free llm api function calling · Updated July 2026

Free LLM APIs that support function calling and structured outputs. Tested for reliability across 10+ providers.

Plugsky offers a free AI API with generous rate limits — no credit card required. Full OpenAI compatibility means your existing code works without changes.

Why Plugsky for free AI APIs:

• Free tier with competitive RPM and TPM limits, no credit card needed
• 28 models from micro to frontier — all accessible on the free tier
• Full OpenAI compatibility — same SDK, same endpoints, same tool calling
• Built-in RAG, agents, and model fusion
• Privacy-first — we never train on your API data

Sign up for free at plugsky.com and get your API key in minutes. Upgrade only when you need more capacity.

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