lean-lsp-mcp

library0.26.2pypypiunverified

A Python library implementing the Model Context Protocol (MCP) for integration with the Lean Theorem Prover's language server (LSP). It enables AI agents to inspect Lean environments, check proofs, get goals, and run commands via the Lean LSP. Version 0.26.2 (current) supports Python >=3.10. Release cadence is active, with frequent updates.

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pip install lean-lsp-mcp

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INSTALL

IMPORT

SIG · LEAN-LSP-MCP

lean-lsp-mcp

ai-mlpythonv0.26.2

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

LeanLspClient

✓ from lean_lsp_mcp.client_utils import LeanLspClient

✗ from lean_lsp_mcp import LeanLspClient

Initialize a Lean LSP client, execute a command (checking a simple equality), and print the resulting goals.

import os from lean_lsp_mcp import LeanLspClient async with LeanLspClient(lean_path=os.environ.get('LEAN_PATH', '')) as client: result = await client.execute_command('example ⊢ 2+2=4') print(result.goals)

Debug

Known issues

breakingThe import path changed from `lean_lsp` to `lean_lsp_mcp` in version 0.20.0. All existing code using `from lean_lsp import ...` will break.

fix

Update imports to `from lean_lsp_mcp import ...`.

affects: >=0.20.0

deprecatedThe `LeanClient` class was renamed to `LeanLspClient` in version 0.25.0. `LeanClient` still works but emits a deprecation warning.

fix

Replace `LeanClient` with `LeanLspClient` in your code.

affects: >=0.25.0

gotchaThe `lean_path` parameter must point to the Lean executable (e.g., `lean` or full path). Passing the workspace folder path will not work.

fix

Set `lean_path` to the path of the `lean` binary, often found at `/path/to/.elan/bin/lean`.

affects: all

Upgrade

Version history

0.26.2latest on PyPI · released May 4, 2026

Audit

Dependencies

pydanticrequiredUsed for data validation and settings management

httpxrequiredHTTP client for communicating with Lean LSP server

Agent activity

20 hits · last 30 days

node

Resources

githubhttps://github.com/oOo0oOo/lean-lsp-mcp ↗

homepagehttps://github.com/oOo0oOo/lean-lsp-mcp ↗