migration-safety SKILL.md skillA
This file is byte-identical to the first copy the registry indexed, one of 4 indexed copies. Same content hash, so the same checks give both the same grade.
migration-safety from jakeselby/agent-harness is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add jakeselby/agent-harness/migration-safety@git:20260929.1af83d7Pins git:20260929.1af83d7 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- jakeselby/agent-harness
- Path
directory/model-citizen/primitives/skills/migration-safety/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260929.1af83d7, committed Sep 29, 2026
- First version recorded
- Sep 28, 2026
- Size
- 3,928 bytes
- Repository stars
- 24
- License
- MIT
Write, review or apply a database schema migration without destroying data. Use for any task that creates or modifies a migration file (Alembic, Prisma, Django, Rails, Flyway, raw SQL), and before applying one to a shared environment.
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
# Migration safety ## Treat every environment as production Staging and demo environments hold real data more often than anyone admits, and a migration that destroys data in staging demonstrates that the same operation would run in production. There is no "it's just staging" exception. **Never write a migration that could silently destroy existing data.** ## Destructive operations — stop and surface to the human Do not generate these autonomously. Describe what you intend and why, and wait for confirmation before writing the file: - `DROP TABLE`, `DROP COLUMN`, `TRUNCATE` — destroys rows or values permanently. - `ALTER COLUMN … TYPE` with a lossy cast — the database rewrites the column; values that cannot be cast are lost. - Removing `NOT NULL` and then dropping the column — same as above. - `DELETE FROM` inside a migration — data loss with no recovery short of a backup. ## Safe patterns **Adding a column.** Add it nullable first, even if the final intent is `NOT NULL`. Backfill in a separate migration or deploy step. Add the constraint only after the backfill is confirmed. Three small migrations beat one that rewrites data and adds a constraint at once. …
Read the whole file at its exact version.
How to install
mdr add jakeselby/agent-harness/migration-safety@sha256:4e0bb46970155628The line at the top of this page pins the label git:20260929.1af83d7, 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_g3ijkpdr76s6ofma)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Sep 28, 2026 and Sep 29, 2026, more than one a day.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260929.1af83d7 latest | 2026-09-29 | 1af83d7 | 3,928 B | A | view · diff |
| git:20260928.ca93e6d | 2026-09-28 | ca93e6d | 3,759 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 (3928 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
jakeselby/agent-harness · 24 stars · license MIT · pushed 2026-10-15 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_g3ijkpdr76s6ofma GET https://markdownregistry.com/api/v1/resolve?ref=jakeselby/agent-harness/migration-safety GET https://markdownregistry.com/api/v1/blob/4e0bb46970155628416442530b8db3e359a5c6429606697b84ed8079b4fd4fd6
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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