The Agent Index

Infrastructure for AI agents. Tools an agent reaches for mid-workflow to do its job. Verified by the builders who use them every day.


  • Anthropic API

    Claude models (Sonnet, Opus, Haiku) via REST API with native tool-use, extended thinking, and MCP support.

    LLM InferenceREST API
  • Google Gemini API

    Gemini 3 Pro and Flash models with native multimodal input, 2M token context, and image generation.

    LLM InferenceREST API
  • Groq

    Ultra-low-latency inference for open models (Llama, Mixtral, Qwen) on custom LPU silicon.

    LLM InferenceREST API
  • OpenAI API

    GPT-4 class models, embeddings, image generation, and the Responses API via REST.

    LLM InferenceREST API
  • Together AI

    Hosted inference for hundreds of open models plus dedicated endpoints and fine-tuning.

    LLM InferenceREST API

The Agent Index is open source. The canonical list lives on GitHub, and every entry on this page is generated from that repo at build time. Contributions are welcome as pull requests. Read the rules before submitting; the bar is sharp, but the review is fast.

Tools are added after they show up in production agent workflows or get strong signal from builders with real usage. Inclusion is the editorial judgment. There is no ranking within categories. Every tool listed has earned its place against the same criterion: can an agent complete its full lifecycle through a fully programmatic path?