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deductive-verification-with-dafny-and-why3 SKILL.md skillA

deductive-verification-with-dafny-and-why3 from outlinedriven/outline-driven-development is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned

mdr add outlinedriven/outline-driven-development/deductive-verification-with-dafny-and-why3@git:20260912.5c5b759

Pins git:20260912.5c5b759 in mdr.lock. Pin the fingerprint instead.

Audit grade: A, 17 of 17 checks passed
Kind: SKILL.md skill
Repository: outlinedriven/outline-driven-development
Path: .devin/skills/deductive-verification-with-dafny-and-why3/SKILL.md
Versions recorded: 2
Latest version: git:20260912.5c5b759, committed Sep 12, 2026
First version recorded: Sep 5, 2026
Size: 5,080 bytes
Repository stars: 55
License: Apache-2.0

Use when an imperative program needs pre-conditions, post-conditions, and loop invariants proved automatically by SMT in Dafny or Why3, short of a tactic prover.

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# Deductive verification with Dafny and Why3

## Contract

| Field | Bound contract |
|---|---|
| Trigger | The task is to prove the pre-conditions, post-conditions, and loop invariants of imperative code with an SMT-backed prover: Dafny for annotate-then-verify on executable code, Why3 for multi-prover goals over WhyML. Methodology stays with proof-driven. |
| Authority | Reversible local: writes only Dafny and WhyML source files, prover configuration, and session files under the project; rollback is version control. No remote mutation. |
| Side effect | Local writes to annotated sources, the Why3 user configuration, and `.why3session.xml` proof sessions. No remote mutation. |
| Done | The module verifies with no unproved obligations: `dafny verify` reports zero errors, or every Why3 goal is Valid and `why3 replay` re-confirms the session. |

## Inputs

- Code to verify: Dafny sources (`.dfy`) or WhyML sources (`.mlw`), new or existing.
- The property set: pre-conditions, post-conditions, loop invariants, and termination measures.
…

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint

mdr add outlinedriven/outline-driven-development/deductive-verification-with-dafny-and-why3@sha256:17a181014acd8f51

The line at the top of this page pins the label git:20260912.5c5b759, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.

Badge

[![mdr](https://markdownregistry.com/badge/art_arkbwimdsilxbvuh.svg)](https://markdownregistry.com/a/art_arkbwimdsilxbvuh)

4 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 2 versions of this file, between Sep 5, 2026 and Sep 12, 2026, about one every 7 days.

version	committed	commit	size	audit
git:20260912.5c5b759 latest	2026-09-12	5c5b759	5,080 B	A	view · diff
git:20260905.fd53e99	2026-09-05	fd53e99	5,049 B	A	view

Audit of the latest version

A 17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.

pass: Frontmatter block present
pass: Frontmatter declares a name
pass: Frontmatter declares a description
pass: Size between 200 bytes and 200 KB (5080 bytes)
pass: No zero-width or bidi control characters
pass: No instruction hidden inside an HTML comment
pass: No link to an exfiltration or paste host
pass: No credential-shaped string
pass: No instruction to send local credentials anywhere
pass: No text hidden with inline styles
pass: No prompt-injection phrasing
pass: No curl or wget piped into a shell
pass: No recursive delete of root, home or parent
pass: No instruction to read or print local credentials
pass: No base64 blob over 200 characters
pass: No link to a raw IP address
pass: No script tag

Source

GitHub

outlinedriven/outline-driven-development · 55 stars · license Apache-2.0 · pushed 2026-09-28 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_arkbwimdsilxbvuh
GET https://markdownregistry.com/api/v1/resolve?ref=outlinedriven/outline-driven-development/deductive-verification-with-dafny-and-why3
GET https://markdownregistry.com/api/v1/blob/17a181014acd8f51269fedf2f7c6e62b0b712347042648ce9c32d32421f93c9b

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

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