🤖 Best AI/ML APIs for Agents

Which AI APIs can agents reliably call, authenticate to, and use programmatically? We rated every major model provider and ML infrastructure tool. Ranked by Agent Native Score — a composite of discoverability, onboarding friction, agent tooling quality, reliability, and pricing model.

OpenAI
llms.txt
85

GPT-4, o1, DALL-E, Whisper, and Embeddings APIs. The most widely adopted AI API with extensive ecosystem support.

Discovery
90
Account creation
80
Agent tooling
90
Reliability
70
Pricing model
75
Structured outputs, function calling, and JSON mode work well. No official MCP server. Reliability has improved but still occasional outages. No free tier (must add payment method).
Groq
Free tier
84

LPU-based LLM inference at 500+ tokens/second. OpenAI-compatible API. Runs Llama, Gemma, Mixtral, Whisper, and other open models.

Discovery
82
Account creation
88
Agent tooling
85
Reliability
78
Pricing model
90
Fastest LLM inference available (500+ tokens/second on LPU). OpenAI-compatible drop-in replacement. Free developer tier with rate limits. Excellent for latency-sensitive agents. No free tier for production.
Anthropic (Claude API)
llms.txt
83

Claude API. State-of-the-art language models with native tool use, computer use, and MCP support built in.

Discovery
90
Account creation
85
Agent tooling
95
Reliability
70
Pricing model
55
Created the MCP protocol. Native tool use is class-leading. Prompt caching reduces costs for agents with long contexts. No free tier. API access occasionally waitlisted.
Cloudflare
Free tier
80

CDN, DDoS protection, DNS, Workers (serverless), KV, R2 storage, AI Gateway, and more. Extensive free tier.

Discovery
85
Account creation
80
Agent tooling
75
Reliability
95
Pricing model
65
Exceptional reliability (99.99%+ uptime). Workers free tier is very useful for agents. API surface is large — agents need scoped tokens to avoid confusion. No official MCP server yet.
Together AI
Free tier
80

Inference API for open-source models (Llama, Mistral, Qwen, etc.). OpenAI-compatible API, fast inference, and fine-tuning support.

Discovery
75
Account creation
88
Agent tooling
80
Reliability
78
Pricing model
82
OpenAI-compatible API for open-source models. Drop-in replacement for agents using OpenAI SDK. Free $1 credit on signup. Competitive pricing vs. proprietary models. Good for cost-conscious agent deployments.
Hugging Face
Free tierllms.txt
78

ML model hub with 500k+ models. Serverless inference API, Spaces for demos, Datasets hub, and Inference Endpoints for dedicated hosting.

Discovery
92
Account creation
85
Agent tooling
72
Reliability
70
Pricing model
70
Largest ML model hub. Serverless Inference API for 150k+ models. Free tier is rate-limited but functional. Has llms.txt. No official MCP server. Inference Endpoints for dedicated hosting (paid).
Replicate
76

Run ML models via REST API — image generation, audio, video, text, and custom models. Pay per prediction, no GPU management.

Discovery
80
Account creation
80
Agent tooling
72
Reliability
70
Pricing model
78
Run any ML model via REST without managing GPUs. Clean API: POST model + inputs, poll for output. GitHub-based signup. Pay-per-prediction. Community models include Flux, Stable Diffusion, Llama. No free tier.

Query this registry from your agent

Add the Agent Native Registry MCP server to get real-time scores and comparisons while your agent works.

claude mcp add agentnative -- npx -y agent-native-registry