leanstral-1-5@eu
Leanstral 1.5 is an updated Lean 4 formal proof engineering model from Mistral AI, optimized for automated theorem proving and autoformalization. It has 119B total parameters with 6.5B active and supports a 256K token context window. It supports native function calling and structured output.
Model facts
- Context window
- 262K tokens
- Maximum output
- 33K tokens
- Cheapest paid input
- free per 1M tokens
- Cheapest paid output
- free per 1M tokens
- Open weights
- no
- Providers
- 1
Capabilities and modalities
tool calling, structured output, text.
Observed price history
- 2026-08-24: free input / free output per 1M tokens
API providers
- Requesty — model id leanstral-1-5@eu; free input / free output per 1M tokens; provider documentation