Editor's pick Open source
Langfuse
Traces, metrics and prompt management for LLM products.
What it is
Open source observability for AI applications: it records every call with its cost and latency, versions prompts outside the code and lets you annotate outputs to build evaluation datasets.
Best for
Knowing exactly what your agent called and what it cost.
What the free plan includes
- 50,000 observability units per month
- Limited retention on the free plan
- Self-hostable alternative with no licence cost
Free plans change often. Confirm the limits on the official page before deciding.
Hugging Face
PickCommunity models, datasets and runnable demos.
Free for public models, datasets and Spaces
Google AI Studio
PickPrototype with the Gemini models from your browser.
Free studio access and a free API tier
NVIDIA NIM
Hosted APIs for AI models optimised by NVIDIA.
Free API credits for prototyping