Gathering Migration 🌲🐻🐕

The drum echoes through the valleys. The conductor stands at the pass, orchestrating two very different strengths. The Bloodhound arrives first with fresh eyes — no assumptions about what's connected, just a nose for dependencies. Then the Bear wakes, receiving a map it didn't draw — no shortcuts, no "I already know where things are." Together they move mountains safely, each with isolated context, each trusting only what it verified itself.

When to Summon

Complex migrations requiring codebase exploration before execution
Moving between systems, libraries, or architectural patterns
Schema changes affecting multiple relationships
Component or API migrations spanning many files
Icon, asset, or content migrations with downstream dependencies
Any migration where you need to understand the territory before moving

IMPORTANT: This gathering is a conductor. It never scouts or migrates directly. It dispatches subagents — one per animal — each with isolated context and an intentional model. The conductor only manages handoffs and gate checks.

The Gathering

SUMMON → DISPATCH → GATE → DISPATCH → GATE → VERIFY
  ↓         ↓        ↓        ↓        ↓        ↓
Spec    Bloodhound  Check    Bear    Check    Final
(self)   (haiku)     ✓     (opus)    ✓     Verify

Animals Dispatched

Order	Animal	Model	Role	Fresh Eyes?
1	🐕 Bloodhound	haiku	Scout dependencies, map territory	Yes — sees only the migration spec
2	🐻 Bear	opus	Execute migration safely	Yes — sees only territory map, not scouting process

Reference: Load references/conductor-dispatch.md for exact subagent prompts and handoff formats

Phase 1: SUMMON

The drum sounds. The valley listens...

The conductor receives the migration request and prepares the dispatch plan:

Clarify the Migration:

What needs to migrate? (data, components, icons, config, conventions...)
From where to where? (old pattern → new pattern)
What downstream dependencies exist?
What does "undo" look like if something goes wrong?

Determine the Bear's domain guide:

Migration Type	Domain Guide
Database schema, tables, D1/SQLite	`domain-database.md`
Component props, API upgrades, imports	`domain-components.md`
Icons, assets, documents, file formats	`domain-content.md`
Config, conventions, dependencies	`domain-general.md`

Confirm with the human, then proceed.

Output: Migration specification, domain guide identified, dispatch plan confirmed.

Phase 2: SCOUT (Bloodhound)

The conductor signals. The Bloodhound puts its nose to the ground...

Agent(bloodhound, model: haiku)
  Input:  migration specification only
  Reads:  bloodhound-scout/SKILL.md (MANDATORY)
  Output: territory map

Dispatch a haiku subagent to scout the codebase. The Bloodhound receives ONLY the migration specification — no pre-analysis, no assumptions. It reads its own skill file and executes its full SCENT → TRACK → HUNT → REPORT → RETURN workflow.

What the Bloodhound maps:

Every reference to the items being migrated
Dependency relationships (what depends on what)
Downstream consumers
Edge cases and unusual usage patterns
Current state counts (how many items, how many references)

Handoff to conductor: Territory map (affected files, dependency graph, edge cases, current state counts, risk assessment).

Gate check: Territory map has: file lists, dependency relationships, item counts, edge cases identified. If incomplete, resume Bloodhound with specific questions.

Phase 3: MIGRATE (Bear)

The Bear wakes. It receives a map it didn't draw...

Agent(bear, model: opus)
  Input:  migration spec + territory map (from Bloodhound)
  Reads:  bear-migrate/SKILL.md + references/{domain-guide} (MANDATORY)
  Output: migration results + file list

Dispatch an opus subagent to execute the migration. The Bear receives the spec and the Bloodhound's territory map — NOT the Bloodhound's scouting process, just its structured output.

What the Bear does:

Preserve original state (branch, backup, or snapshot)
Execute migration in manageable chunks
Validate after each chunk
Verify item counts match (source vs destination)
Run integrity checks (references resolve, imports work, no orphans)

Handoff to conductor: Migration results (items migrated, items skipped, validation reports), file list.

Gate check:

pnpm install
gw dev ci --affected --fail-fast --diagnose

Must compile and pass. If it fails, resume Bear with the error.

Phase 4: VERIFY

The journey ends. The conductor confirms safe arrival...

Validation Checklist:

Bloodhound: All dependencies mapped
Bloodhound: All references found
Bloodhound: Edge cases documented
Bear: Original state preserved (branch, backup, or snapshot)
Bear: Item counts match (source vs destination)
Bear: Integrity checks pass (references resolve, imports work, no orphans)
Bear: Tests pass (gw dev ci --affected)
Bear: Rollback path documented

Completion Report:

🌲 GATHERING MIGRATION COMPLETE

Migration: [Description]

DISPATCH LOG
  🐕 Bloodhound (haiku) — [territory mapped, X files identified, Y dependencies found]
  🐻 Bear (opus)         — [Z items migrated, domain guide: {guide}]

GATE LOG
  After Bloodhound: ✅ territory map complete
  After Bear:       ✅ compiles clean, migration verified
  Final CI:         ✅ gw dev ci --affected passes

MIGRATION RESULTS
  Items migrated: [count]
  Items skipped: [count, reason]
  Item count match: ✅ [source] = [dest]
  Integrity checks: ✅
  Rollback: [branch/backup location]

Everything found its new home.

Conductor Rules

Never Do Animal Work

The conductor dispatches. It does not scout dependencies or execute migrations.

Fresh Eyes Are a Feature

The Bear receives the territory map, not the Bloodhound's scouting process. It trusts the map but verifies what it finds during migration.

Gate Every Transition

Territory map must be complete before Bear starts. CI must pass after Bear finishes.

Resume, Don't Restart

If a gate check fails, resume the failing agent. The Bear especially benefits from resumption — it has the migration context and can fix issues faster than starting fresh.

Anti-Patterns

The conductor does NOT:

Scout the codebase itself
Execute migration steps directly
Let Bear start without a complete territory map
Skip count validation (source must equal destination)
Skip rollback documentation

Quick Decision Guide

Migration Scope	Strategy
Simple rename (< 5 files)	Bear only (no Bloodhound needed)
Cross-cutting migration (5-50 files)	Standard: Bloodhound → Bear
Large migration (50+ files)	Bloodhound → Bear with chunked execution
Unknown scope ("migrate X")	Always start with Bloodhound

When no single animal suffices, the gathering answers. 🌲🐾

gathering-migration