Leanstral
✅ ActiveMistral model specialized for theorem proving, formal reasoning, and Lean workflows
Provider list prices
Context Window
128K
Input Price
$0.20/1M
Output Price
$0.60/1M
Released
Mar 19, 2026
Capabilities
textcodereasoningformal-methods
Crazyrouter API catalogue
Not confirmed in the current default-group API catalogue.
Catalogue checked: 2026-10-10T14:22:39+00:00. USD per 1M tokens, default group. The first context tier is shown; long contexts may cost more. This is a gateway catalogue snapshot, not a provider release announcement.
Get API Access →Current API modelsVersion History
Jun 30, 2026Update
Leanstral 1.5 (labs-leanstral-1-5) released with improved SFT mixture quality and extended long-context reasoning for Lean 4 proof engineering
Jun 30, 2026Deprecation
The Leanstral 1.5 labs model is scheduled for retirement on September 30, 2026
Mar 19, 2026New Release
Leanstral released for formal mathematics and Lean-assisted reasoning tasks