schema-migration-safety

schema-migration-safety is a skill for Claude Code from yuchi-chang/no-cape. It costs 28 tokens per session (338 once invoked), scanned A, original, no licence file.

A safety guide for database schema migrations, which are changes to tables, columns, indexes, or rules in a database that may already contain real data.

In plain words
What is it for?
Use it before writing migrations or changing database tables, columns, indexes, or constraints.
Why use it?
It helps identify risks before a database change could damage, lose, or make existing data harder to use.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the no-cape plugin — 14 skills, 1 command, 3 hooks shipped together

Good fit Use it before writing migrations or changing database tables, columns, indexes, or constraints.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/yuchi-chang/no-cape/schema-migration-safety
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.

Any agent
npx skills add yuchi-chang/no-cape --skill schema-migration-safety
Clone the repo
git clone --depth 1 https://github.com/yuchi-chang/no-cape

Made for: Claude Code.

Or install no-cape, the plugin that ships this one along with the rest of its 14 skills, 1 command, 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 schema-migration-safety

README.md
[![agentmods](https://agentmods.dev/badge/skills/yuchi-chang/no-cape/schema-migration-safety/github.svg)](https://agentmods.dev/skills/yuchi-chang/no-cape/schema-migration-safety)
Your own site
<a href="https://agentmods.dev/skills/yuchi-chang/no-cape/schema-migration-safety"><img src="https://agentmods.dev/badge/skills/yuchi-chang/no-cape/schema-migration-safety/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for schema-migration-safety

Your own site · 80×15
<a href="https://agentmods.dev/skills/yuchi-chang/no-cape/schema-migration-safety"><img src="https://agentmods.dev/badge/skills/yuchi-chang/no-cape/schema-migration-safety.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 28 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 338 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 5.1 $0.00028 $0.00338
Opus 5 $0.00014 $0.00169
Sonnet 5 $0.00006 $0.00068
Haiku 4.5 $0.00003 $0.00034

Measured 10d ago against content hash 3ffa4709b078, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

schema-migration-safety 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 10d ago.

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.

skills/schema-migration-safety/SKILL.md · 31 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 10d ago First seen · 31 lines · 28 tokens per session scan A 3ffa4709b078

Subscribe to this mod's changes

schema-migration-safety is a skill published in the GitHub repository yuchi-chang/no-cape (2 stars, last pushed 1mo ago), with no licence file. It adds 28 tokens to every session and 338 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 2026-08-31.

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