migrate

migrate is a skill for Claude Code from angad-kandhari/deliberate. It costs 74 tokens per session (1,580 once invoked), scanned A, original, Apache-2.0.

Guidance for making database, framework, API, naming, and data migrations in small steps. A migration is a change that moves an existing system from one version or structure to another.

In plain words
What is it for?
Use it for schema changes, API upgrades, renames, data backfills, feature-flagged cutovers, and other changes that cannot be deployed atomically.
Why use it?
It helps avoid breaking users by keeping old and new paths working together until the transition is tested and complete.

Skill for Claude Code

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

Part of the deliberate plugin — 11 skills, 1 hook shipped together

Good fit Use it for schema changes, API upgrades, renames, data backfills, feature-flagged cutovers, and other changes that cannot be deployed atomically.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/angad-kandhari/deliberate/migrate
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 angad-kandhari/deliberate --skill migrate
Clone the repo
git clone --depth 1 https://github.com/angad-kandhari/deliberate

Made for: Claude Code.

Or install deliberate, the plugin that ships this one along with the rest of its 11 skills, 1 hook.

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 migrate

README.md
[![agentmods](https://agentmods.dev/badge/skills/angad-kandhari/deliberate/migrate.svg)](https://agentmods.dev/skills/angad-kandhari/deliberate/migrate)
Your own site
<a href="https://agentmods.dev/skills/angad-kandhari/deliberate/migrate"><img src="https://agentmods.dev/badge/skills/angad-kandhari/deliberate/migrate.svg" alt="Measured on agentmods" height="20"></a>
Per session 74 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,580 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 original 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 $0.00074 $0.01580
Opus 5 $0.00037 $0.00790
Sonnet 5 $0.00015 $0.00316
Haiku 4.5 $0.00007 $0.00158

Measured 7d ago against content hash 8ebb63668555, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

migrate 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 7d 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/migrate/SKILL.md · 169 lines

How it starts

The opening of the file, as written. The whole thing — 169 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Migrate

Migration skill for LLM coding agents. Load this for non-trivial migrations: database schema changes, framework upgrades, API version bumps, rename rollouts, data backfills, or any change that can't land in a single atomic deploy.

Where deliberate keeps code honest, this skill keeps transitions honest. Counters the big-bang rewrite, the half-finished migration, and the "we'll clean up the old path later" that never happens.


1. Incremental By Default

Big-bang migrations fail. Plan for coexistence.

The question isn't "how do I switch from old to new?" It's "how do I run old and new side by side long enough to verify, then cut over?"

Default migration shape:

  1. Add the new path alongside the old. Don't remove anything yet.
  2. Dual-write / dual-read where relevant. Old and new stay in sync.
  3. Migrate callers one at a time. Verify each.
  4. Backfill any historical data.
  5. Cut over reads to the new path.
  6. Remove the old path only after the new path has been stable in production.

A migration that requires all callers to update in the same PR is not a migration. It's a rewrite, and it will stall.

Test: Can I deploy each step independently, and roll any single step back?


2. Write the Rollback Before You Write the Migration

If you can't undo it, you can't ship it.

For every migration step, name the rollback:

  • Schema add: drop the column. Safe if nothing writes to it yet.
  • Schema drop: restore from backup. Often not safe - push drops to the end.
  • Data backfill: idempotent, so reruns don't double-count. Or: clearly one-way, with a rollback plan documented.
  • Code cutover: feature flag, so reverting is a config change, not a deploy.

If the rollback is "restore the DB," your migration is too big. Break it up.

Test: If this breaks in production at 3am, how do I undo it without paging the DBA?


3. Make Schema Changes Safe, Not Fast

Every destructive schema change is a minefield.

Read the full file on GitHub · 169 lines

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. 7d ago First seen · 169 lines · 74 tokens per session scan A 8ebb63668555

Subscribe to this mod's changes

migrate is a skill published in the GitHub repository angad-kandhari/deliberate (2 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 74 tokens to every session and 1,580 once invoked, about $0.0004 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.