migrate

A migration command that moves a system from one design to another through separate deployment phases. The phases are expand, backfill, dual-write, switch, and contract, covering database, framework, runtime, API, and event-schema changes.

In plain words
What is it for?
Use it to plan and execute multi-deployment migrations, map current and target data shapes and their readers and writers, and track risks such as locks, backfill cost, and client release timing.
Why use it?
It breaks a potentially risky migration into smaller steps so each phase can be deployed and checked independently.

Command

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 commands/lugassawan/swe-workbench/migrate
Clone the repo
git clone --depth 1 https://github.com/lugassawan/swe-workbench
Per session 27 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 491 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00027 $0.00491
Opus 5 $0.00014 $0.00246
Sonnet 5 $0.00005 $0.00098
Haiku 4.5 $0.00003 $0.00049

Measured 2d ago against content hash e7e491785746, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d 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.

commands/migrate.md · 21 lines

What it actually says

Migration: $ARGUMENTS

If $ARGUMENTS contains a ticket reference, invoke swe-workbench:ticket-context first and prepend its structured summary to the delegation context below. Skip if $ARGUMENTS is free-text with no recognizable ref. (Trigger patterns are defined in that skill's "When to invoke" section.)

Delegate to the swe-workbench:migrator subagent. Its output must include:

  1. Class — DB schema, framework upgrade, runtime, API/contract, or event-schema. Determines the dominant hazard.
  2. Shapes — current (A) and target (B) stated precisely, plus the call-site map (readers and writers enumerated).
  3. Strategy — chosen approach (online vs. offline, phased vs. big-bang) with rationale; deferred to swe-workbench:senior-engineer if ambiguous.
  4. Phase plan — five phases (Expand → Backfill → Dual-write → Switch → Contract), each with what-happens / reversible-by / gate-to-advance slots filled in.
  5. Risks — lock duration, backfill cost on a representative replica, sunset window vs. client release cycle.

Absolute rule: phases ship independently — never bundle two phases in one deployment.

Plan output: If you (the orchestrator) author a plan based on the subagent's response and that plan modifies the codebase (fix / make / implement) — whether saved to a plan file or passed to ExitPlanMode — first activate swe-workbench:workflow-development in Mode A and embed the rendered ## Workflow section in the plan per skills/workflow-development/templates/plan-workflow-section.md. Run the skill's project-detection (git branch -a, git log --oneline -20, Makefile grep, PR-template lookup) so the placeholders are substituted from this repo, not left as [[detect:…]]. Skip Mode A if the plan is pure analysis, design recommendation, or any output that does not introduce file edits — the Workflow section's phases (Branch / Verify / Deliver) do not apply.

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. 2d ago First seen · 21 lines · 27 tokens per session scan A e7e491785746

Subscribe to this mod's changes

migrate is a command published in the GitHub repository lugassawan/swe-workbench (2 stars, last pushed 2d ago), licensed MIT. It adds 27 tokens to every session and 491 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.