Migration Pattern — MCP recommendations

Pattern: Migration
Component: mcps.md
Version: 1.1 | Updated: 2026-07-29

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Purpose

Least-privilege MCP servers for the Migration pattern. Keep mcpServers: {} until a human enables stubs after MCP when and how.

Recommended MCPs

MCP	Why for this pattern
GitHub	PR/plan evidence
PostgreSQL	Schema/data checks (read-only first)
Docker	Optional — local migrate jobs
Kubernetes	Optional — cutover workloads

When to enable for Migration

PostgreSQL/Docker/Kubernetes MCPs are for read-only parity checks and rollout status — never for irreversible drops without a signed phase gate.

Enable rules (this pattern)

1. Database MCP starts SELECT-only; DDL requires an approved phase ticket
2. Never commit tokens; map secrets outside git
3. Record allowlist + data class in MODEL_POLICY / SoA before write tools
4. Revoke cluster write tools before the verify window ends

Anti-patterns

• Running DROP via MCP because the dual-write “looked fine”
• Embedding connection strings in MCP config committed to git
• Skipping digest pins because the local migrate job succeeded

Checklist

• Migration MCPs mapped to env secrets outside git
• Unused servers remain disabled after the migration gate
• Injection / tool PEP reviewed if tools can act