LLM observability and evals for AI agents
2 APIs compared on price, free tier, MCP support and real usage. Prices from the vendors' pricing pages, checked Oct 9, 2026.
| API | Free | Price | SDK downloads / wk | GitHub stars | MCP |
|---|---|---|---|---|---|
| Opik Platform for tracing, testing, and evaluating AI agents and LLM applications. |
25k spans/month, 60-day retention | Free plan · paid from $19/mo | — | — | |
| Pydantic Logfire Observability platform for AI agents, services, and infrastructure with tracing, logging, and metrics. |
10 million spans, logs, or metrics per month | Free plan · paid from $49/mo | — | — |
Other categories
Web search APIs Scraping and crawling Browser automation (cloud) Code sandboxes Memory for agents Vector databases LLM gateways and routers Email sending Voice (speech-to-text, text-to-speech) Payments for agents Blockchain RPC and node providers DEX swap and liquidity APIs Crypto market and on-chain data 3D model generation Image generation APIs Sound effects and music generation Video generation APIs Model hosting and inference Embeddings and rerank Document parsing and OCR Error tracking and analytics Databases and backends Auth and user accounts File storage and media CDN Hosting and deployment SMS, chat and notifications Integrations and automation Business apps with APIs Maps and location Wallets, tokens and NFTs