# Lean

**Canonical:** https://apis.io/providers/lean/  
**Website:** https://lean-lang.org/  
**APIs profiled:** 1

Lean is an open-source theorem prover and programming language based on dependent type theory, designed for formal verification of mathematics and software. It supports interactive proof development and is used by mathematicians and computer scientists.

## Kin Score — 11.4 / 100 (emerging)

Scored 2026-08-30 under rubric 0.17.2. Trend: flat (+0.0 from 11.4).

| Facet | Score |
|---|---|
| Discoverability | 50.0 |
| Contract Quality | 0.0 |
| Governance | 0.0 |
| Contract Governance | 0.0 |
| Operational Transparency | 10.5 |
| Developer Ergonomics | 9.5 |
| Commercial Clarity | 15.8 |
| Access Clarity | 15.8 |

## Agent readiness — 2.5 (human-only)

| Dimension | Value |
|---|---|
| Spec Presence | no |
| Agentic Access | no |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | no |
| Idempotency | no |
| Error Semantics | no |
| OpenAPI Examples | no |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |

## Access

Freemium — onboarding: unknown, pricing: freemium, trial: no (confidence: medium).

## APIs (1)

- **Lean** — Lean theorem prover and programming language for formal verification of mathematics and software.

## Security (1)

- **Lean Domain Security** — TLSv1.3 · HSTS · DNSSEC

## Plans (1)

- **Lean Plans Pricing**

## Tags

Dependent Types, Formal Verification, Programming Language, Theorem Prover

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/lean/). Scores are computed from the provider's own public artifacts under a published rubric.