llm-lib Demo
Try one JavaScript library against OpenAI, Anthropic or Gemini models by picking a provider and pasting a key.
Artifact by Simon Willison
Use it
Opens tools.simonwillison.net in a new tab. Nothing to install.
- You provide
- Provider, model, prompt, API key
- You get
- Model response
- Account
- No sign-up needed
- AI
- AI-powered; you bring your own API key
- Your input
- Not stated: check the tool's privacy notes before using private data
- Price
- Free to use
- Made with
- AI-built app
- Source
- Open source
- Link check
- Answered on Oct 31, 2026
About
Category: Developer tools · api playground
Reviews
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Details
- Auth
- API key
- License
- Apache-2.0
- Repository
- github.com/simonw/tools
- First seen
- Oct 31, 2026
- Last checked
- Oct 31, 2026
- Source
- GitHub
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Cite this page
llm-lib Demo: free online tool. Agent Mart. https://agentmart.dev/artifacts/llm-lib-demo (last updated 2026-10-31)