maintain-formal-verification-skill SKILL.md skillA
maintain-formal-verification-skill from backnotprop/pstack is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add backnotprop/pstack/maintain-formal-verification-skill@git:20261019.6ddf66aPins git:20261019.6ddf66a in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- backnotprop/pstack
- Path
skills/maintain-formal-verification-skill/SKILL.md- Versions recorded
- 1
- Latest version
- git:20261019.6ddf66a, committed Oct 19, 2026
- Size
- 7,012 bytes
- Repository stars
- 2,481
- License
- MIT
Bring a project's formal verification back in line with the code after the code changes: find the commits that touched verified code, update the model, harness, or properties to describe the code as it is now, rerun, and say whether each failure is drift in the verification or a bug in the code. Use for /maintain-formal-verification-skill, "is the model still true to the code", or after merges and refactors that touched verified code without rechecking it.
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
# Maintain a formal verification skill A formal check proves a property of what it describes. When the code changes and the verification does not, the check can keep passing while it describes code that no longer exists. That pass is the dangerous case, because it looks like a proof. This skill is the upkeep loop for a verify skill that `/create-formal-verification-skill` generated, or for any project-local skill that runs a model checker, prover, or code-level verifier against named code. The project-local skill handles a change that an agent makes while it uses that skill. This skill handles the changes that skipped it: merges, edits made without the skill, and drift that builds up across many commits. ## Outcomes Give each check one outcome, and say which: - **in sync**: no change since the last sync alters what the check describes, and the check passes. - **updated**: the code changed, the verification now describes the new code, and the check passes. - **bug**: the verification describes the current code, and the code breaks the property. This is a finding about the code. It is not drift. …
Read the whole file at its exact version.
How to install
mdr add backnotprop/pstack/maintain-formal-verification-skill@sha256:0c96f54293542d38The line at the top of this page pins the label git:20261019.6ddf66a, 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.
[](https://markdownregistry.com/a/art_nnllqqpqtn3shezg)
1 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Oct 19, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (7012 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
backnotprop/pstack · 2,481 stars · license MIT · pushed 2026-10-20 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_nnllqqpqtn3shezg GET https://markdownregistry.com/api/v1/resolve?ref=backnotprop/pstack/maintain-formal-verification-skill GET https://markdownregistry.com/api/v1/blob/0c96f54293542d3818b68754562b338073958781a9684454611dca37592e2d2c
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.
More from backnotprop/pstack
Every file in backnotprop/pstack