prove

prove is a command for coding agents from cameronfreer/lean4-skills. It costs 12 tokens per session (3,050 once invoked), scanned A, original, MIT.

A guided Lean 4 command for proving mathematical theorems one cycle at a time, with checkpoints and opportunities to escalate when progress stops. The Lean checker verifies whether proposed proofs are valid.

In plain words
What is it for?
Use it to work through a theorem in a file, repair Lean build errors, or enable deeper help when a proof becomes stuck.
Why use it?
It breaks difficult proving work into reviewable stages and can focus on fixing build errors without filling unfinished proof placeholders.

Command

Part of the lean4 plugin — 1 skill, 12 commands, 4 agents, 3 hooks shipped together

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 commands/cameronfreer/lean4-skills/prove
Clone the repo
git clone --depth 1 https://github.com/cameronfreer/lean4-skills

Or install lean4, the plugin that ships this one along with the rest of its 1 skill, 12 commands, 4 agents, 3 hooks.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for prove

README.md
[![agentmods](https://agentmods.dev/badge/commands/cameronfreer/lean4-skills/prove.svg)](https://agentmods.dev/commands/cameronfreer/lean4-skills/prove)
Your own site
<a href="https://agentmods.dev/commands/cameronfreer/lean4-skills/prove"><img src="https://agentmods.dev/badge/commands/cameronfreer/lean4-skills/prove.svg" alt="Measured on agentmods" height="20"></a>
Per session 12 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,050 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 $0.00012 $0.03050
Opus 5 $0.00006 $0.01525
Sonnet 5 $0.00002 $0.00610
Haiku 4.5 $0.00001 $0.00305

Measured yesterday against content hash 56dff304bbd0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

prove scanned grade A with 0 findings 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 yesterday.

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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/lean4/commands/prove.md · 238 lines

How it starts

The opening of the file, as written. The whole thing — 238 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Lean4 Prove

Guided, cycle-by-cycle theorem proving. Asks before each cycle, supports deep escalation, and checkpoints your progress.

Usage

/lean4:prove                         # Start guided session
/lean4:prove File.lean               # Focus on specific file
/lean4:prove --repair-only           # Fix build errors without filling sorries
/lean4:prove --deep=stuck            # Enable deep escalation when stuck

Invocation Contract

Interpret this command's inputs per the Command Invocation Contract.

Primary path (hook-validated): If a validated-invocation block for this command appears in context, treat it as the authoritative interpretation of parser-decidable inputs and do not re-parse the raw invocation text for those inputs. Start by reading all parser-decided fields from the block. Emit the final Resolved Inputs summary from the block values. See Validated Invocation Block.

Fallback path (other hosts): If no validated-invocation block is present, parse the raw invocation text against this command's input table before Phase 1.

Startup requirements:

  1. Emit a Resolved Inputs block with explicit values, defaults, coercions, ignored flags, and startup validation errors.
  2. Refuse to start on startup validation errors.
  3. Persist any user-approved adjustments as session state so later cycles follow the updated configuration rather than the initial prose alone.

Inputs

Arg Required Default Description
scope No all Specific file or theorem to focus on
--repair-only No false Fix build errors only, skip sorry-filling
--planning No ask ask (prompt at startup), on, or off
--review-source No internal internal, external, both, or none
--review-every No checkpoint N (sorries), checkpoint, or never
--checkpoint No true Create checkpoint commits after each cycle
--deep No never never, ask, stuck, or always
--deep-sorry-budget No 1 Max sorries per deep invocation
--deep-time-budget No 10m Advisory: scopes deep-mode subagent work. Not tracked or enforced.
--max-deep-per-cycle No 1 Max deep invocations per cycle
--deep-snapshot No stash V1: stash only
--deep-rollback No on-regression on-regression, on-no-improvement, always, or never
--deep-scope No target target or cross-file
--deep-max-files No 1 Max files per deep invocation
--deep-max-lines No 120 Max added+deleted lines per deep invocation
--deep-regression-gate No strict strict (auto-abort on regression) or off
--batch-size No 1 Sorries to attempt per cycle
--commit No ask ask (prompt before each commit), auto, or never
--golf No prompt prompt, auto, or never

Read the full file on GitHub · 238 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. yesterday Changed · +8 lines 56dff304bbd0
  2. 5d ago First seen · 230 lines · 12 tokens per session scan A 48c084274b86

Subscribe to this mod's changes

prove is a command published in the GitHub repository cameronfreer/lean4-skills (428 stars, last pushed yesterday), licensed MIT. It adds 12 tokens to every session and 3,050 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.