LeanProbe AGENTS.md

A project instruction file for LeanProbe, a Python package, command-line tool, and MCP server that lets an AI agent check Lean code. Lean is a proof-assistant programming language used to formally verify mathematics and software properties.

In plain words
What is it for?
Use it when developing LeanProbe, running its linting, type checks, and tests, or integrating its Lean verification service with an AI agent.
Why use it?
It explains how to set up the repository, run its checks, and use the bundled agent skill, reducing mistakes when changing or testing the project.

Instructions file for CodexOpenCode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/epfl-lara/leanprobe/agents-md
Clone the repo
git clone --depth 1 https://github.com/epfl-lara/LeanProbe

Made for: Codex, OpenCode.

Per session 1,005 This file is loaded in full into every session.
When invoked 1,005 The same file — it is already loaded in full.
Security scan B 1 finding. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.01005 $0.01005
Opus 5 $0.00502 $0.00502
Sonnet 5 $0.00201 $0.00201
Haiku 4.5 $0.00101 $0.00101

Measured 2d ago against content hash 0437e71927bd, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

LeanProbe AGENTS.md scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Enumerates other installed skillsmediumAgent snooping

Other skills' SKILL.md files reveal prompts, capabilities and secrets that should be invisible to peers.

lean-probe install-skill --skills-dir ./.claude/skills # install into an explicit skills root
AGENTS.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Two kinds of "agent" relate to this repo:

  1. Agents using LeanProbe — an LLM agent that calls the LeanProbe MCP server to verify Lean. The usage contract lives in the LeanProbe skill (src/lean_probe/skill/SKILL.md). Install it into Claude Code / Codex with lean-probe install-skill (see below), or read it directly.
  2. Agents/contributors working on this repo — keep reading.

Working on this repo

LeanProbe is a Python package (src/lean_probe/) exposing a Python API, a CLI, and an MCP stdio server, backed by LeanInteract.

Setup

python -m venv .venv && source .venv/bin/activate
python -m pip install -U pip
python -m pip install -e ".[dev]"

Checks (all must pass; CI runs these):

ruff check src tests          # lint
ruff format --check src tests # formatting (run `ruff format src tests` to fix)
mypy src
pytest -q                     # unit tests use a fake LeanInteract backend

The optional real-LeanInteract test is gated and needs Lean/Lake + a built project:

LEAN_PROBE_RUN_INTEGRATION=1 pytest tests/test_integration.py -q

Module layout: segmentation (file → header + declaration chunks), projects (Lake/REPL discovery), errors (error codes + hints), payloads (response shaping, feedback_lean, the shared ok logic), sessions (LeanInteract lifecycle + the single-shot run_command), probe (the LeanProbe orchestrator), skills (install the bundled skill into agent clients). core is a backwards-compatible facade that re-exports the public names. The agent-facing skill is shipped as package data at skill/SKILL.md so pip install lean-probe carries it (no repo checkout needed to run lean-probe install-skill).

Conventions:

  • Keep LeanProbe independent of downstream projects (no project-specific code).
  • The public Python API (LeanProbe, LeanIncrementalSegment, segment_file) is importable from the package root — keep it backwards compatible.
  • If you change tool semantics, payload fields, or tool names, update the skill (src/lean_probe/skill/SKILL.md) and the server instructions/TOOL_NAMES in mcp_server.py together (a test asserts the tool table in the skill matches the server's TOOL_NAMES).
  • Release: bump version in pyproject.toml, update CHANGELOG.md, then push a vX.Y.Z tag — release.yml builds and publishes to PyPI.

Read the full file on GitHub · 85 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 85 lines · 1,005 tokens per session scan B 0437e71927bd

Subscribe to this mod's changes

LeanProbe AGENTS.md is an instructions file published in the GitHub repository epfl-lara/LeanProbe (4 stars, last pushed 2mo ago), licensed MIT. It adds 1,005 tokens to every session, about $0.0050 per session on Opus 5. A static security scan graded it B with 1 finding (enumerates other installed skills). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.