drift-canary SKILL.md skillA
This file is byte-identical to the first copy the registry indexed. Same content hash, so the same checks give both the same grade.
drift-canary from thecolliery/coalmine is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add thecolliery/coalmine/drift-canary@git:20260922.b3be1e7Pins git:20260922.b3be1e7 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- thecolliery/coalmine
- Path
skills/drift-canary/SKILL.md- Versions recorded
- 5
- Latest version
- git:20260922.b3be1e7, committed Sep 22, 2026
- First version recorded
- Aug 7, 2026
- Size
- 3,393 bytes
- Repository stars
- 14
- License
- Apache-2.0
Compatibility and schema drift canary — checks for database schema migration safety, breaking API contract changes, serializable payload mismatches, and backward compatibility drift. Triggers on keywords: "/drift-canary", "drift-canary", "contract drift", "breaking changes". Use when changing DB schemas, API contracts, serialized payloads, or required config keys.
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
# Drift Canary (Contract & Schema Drift Audit) <!-- SHARED:LANGUAGE_HEADER --> Audit code to ensure changes do not break backward compatibility or cause database/API mismatches. ## Auditing Categories 1. **Breaking Schema Migrations** — dropping columns, changing types, or adding non-null columns without defaults (crashes on deploy). 2. **API Contract breaking changes** — modifying existing REST/GraphQL properties, removing endpoints, or adding required query fields that break old clients. 3. **Serialization mismatches** — editing properties in serialized payloads (JSON, Protobuf, XML) without deserialization fallbacks. 4. **Library Contract Drift** — changing a public method signature in a shared library without a deprecated wrapper. 5. **Environment Configuration drift** — introducing new required config keys (`.env` / OS vars) without defaults or fallback. Expand/contract migration rules, per-format serialization fallbacks, and the breaking-vs-additive API checklist: read `references/checks.md` before scanning. **Scope:** honor `.coalmine.json` `schemaPaths` / `migrationDirs` if set — scan those globs/dirs; else infer by inspecting the repo. ## Discipline …
Read the whole file at its exact version.
How to install
mdr add thecolliery/coalmine/drift-canary@sha256:a00d04a4423add91The line at the top of this page pins the label git:20260922.b3be1e7, 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_b63ghleuuj6dflkq)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 5 versions of this file, between Aug 7, 2026 and Sep 22, 2026, about one every 11 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260922.b3be1e7 latest | 2026-09-22 | b3be1e7 | 3,393 B | A | view · diff |
| git:20260922.948eedb | 2026-09-22 | 948eedb | 3,300 B | A | view · diff |
| git:20260821.c38e734 | 2026-08-21 | c38e734 | 3,220 B | A | view · diff |
| git:20260821.583c32b | 2026-08-21 | 583c32b | 3,070 B | A | view · diff |
| git:20260807.4ab4ef9 | 2026-08-07 | 4ab4ef9 | 2,669 B | A | view |
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 (3393 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
thecolliery/coalmine · 14 stars · license Apache-2.0 · pushed 2026-10-19 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_b63ghleuuj6dflkq GET https://markdownregistry.com/api/v1/resolve?ref=thecolliery/coalmine/drift-canary GET https://markdownregistry.com/api/v1/blob/a00d04a4423add91517f7306d424e0fcddcb436d449895c1fedc5ea73c1bae70
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 thecolliery/coalmine
Every file in thecolliery/coalmine