db-migration

db-migration is a skill for Claude Code from lncrawl/lightnovel-crawler. It costs 54 tokens per session (1,297 once invoked), scanned A, original, GPL-3.0.

A guide for changing a database schema, which is the structure of stored data, in the lncrawl project. It covers model fields, Alembic migrations, development migration commands, and PostgreSQL or SQLite differences.

In plain words
What is it for?
Use it when adding or changing a data-model field, or when writing or reviewing a database migration.
Why use it?
It helps keep application models and database structure in sync while accounting for differences between database systems. It also covers migrations that keep enum values aligned.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

About the project

Lightnovel Crawler is a tool that retrieves web novels from online sources and turns their chapters into e-books. It is for readers who want personal backups or a private library with browser reading, translations, progress tracking, and scheduled updates. The catalogue add-ons support operating its crawler and library workflows.

lncrawl/lightnovel-crawler · 2,584 stars · on GitHub · lncrawl.bitanon.dev

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.

agentmods
npx agentmods add skills/lncrawl/lightnovel-crawler/db-migration
Any agent
npx skills add lncrawl/lightnovel-crawler --skill db-migration
Clone the repo
git clone --depth 1 https://github.com/lncrawl/lightnovel-crawler

Made for: Claude Code.

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 db-migration

README.md
[![agentmods](https://agentmods.dev/badge/skills/lncrawl/lightnovel-crawler/db-migration.svg)](https://agentmods.dev/skills/lncrawl/lightnovel-crawler/db-migration)
Your own site
<a href="https://agentmods.dev/skills/lncrawl/lightnovel-crawler/db-migration"><img src="https://agentmods.dev/badge/skills/lncrawl/lightnovel-crawler/db-migration.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,297 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00054 $0.01297
Opus 5 $0.00027 $0.00648
Sonnet 5 $0.00011 $0.00259
Haiku 4.5 $0.00005 $0.00130

Measured 6d ago against content hash 3a0342af373d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

db-migration 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 6d 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.

.claude/skills/db-migration/SKILL.md · 78 lines

The source is not reproduced here

Licensed GPL-3.0

The repository is licensed GPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

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. 6d ago First seen · 78 lines · 54 tokens per session scan A 3a0342af373d

Subscribe to this mod's changes

db-migration is a skill published in the GitHub repository lncrawl/lightnovel-crawler (2,584 stars, last pushed 5d ago), licensed GPL-3.0. It adds 54 tokens to every session and 1,297 once invoked, about $0.0003 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 2026-08-30.

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