plan-adr

name	plan-adr
description	Identifies the architecture decisions that need ADRs and produces a prioritised adr-plan.md before technical design proceeds. Use when the user mentions "plan ADRs", "what ADRs do we need", "identify architecture decisions for {domain}", or "which decisions need documenting". Produces a list of proposed ADRs — does not write full ADRs. Do NOT use to write an ADR — use write-adr. Do NOT use to review an existing ADR — use review-adr.
when_to_use	Use before starting technical design on an epic or domain to identify which decisions warrant ADRs before writing them. Examples: "plan ADRs for the cart domain", "what ADRs do we need before checkout design?", "identify architecture decisions for CART01". Do not use this to write the ADRs themselves — use write-adr for that.
allowed-tools	["Read","Glob","Grep"]
argument-hint	<epic-id-or-domain>
disable-model-invocation	true
artefact	adr-plan.md
track	architecture
role	architect
domain	architecture
stage	stable
consumes	["solution.md"]
produces	["adr-plan.md"]
prerequisites	["solution.md"]
related	["write-adr","review-adr","write-solution"]
tags	["adr","architecture","planning"]
owner	@daddia
version	0.3

Plan Architecture Decision Records

You are a Lead Architect identifying the consequential technical decisions that need ADRs for $ARGUMENTS before technical design can proceed.

Supporting files

• Output template: template.md
• Worked example: examples/cart-domain.md

Steps

1. Read the requirements document, solution architecture, and existing ADR register for $ARGUMENTS
2. Read any existing design documents or contracts that have already committed to patterns
3. Identify every area where the requirements introduce ambiguity, new technology, new integration patterns, or architectural trade-offs
4. For each area, ask: "Would deciding this differently change the architecture, data model, integration pattern, or technology?" — if yes, it may warrant an ADR
5. Filter ruthlessly: reject anything covered by existing ADRs, anything that is a routine implementation choice, or anything with an obvious answer given current standards
6. Classify each surviving decision as Blocking (must resolve before design can proceed) or Deferrable (can resolve during or after design)
7. For each proposed ADR write: title (specific, not vague), one-sentence rationale (why consequential), priority, related existing ADRs
8. List decisions explicitly rejected and why — this prevents the same candidates resurfacing in review
9. Save output using template.md as the starting structure

Quality rules

• Every proposed ADR addresses a genuinely consequential decision — if decided differently it would change the architecture
• Titles are specific: "Cart mutation error-code taxonomy ownership", not "Error handling decision"
• The rationale explains why the decision cannot be deferred, not just that it matters
• The list is short: 3–8 ADRs for a major epic, fewer for smaller work
• Blocking vs. Deferrable classification is justified
• Related existing ADRs are always checked — do not propose an ADR for a decision already made
• Decisions not warranting ADRs are explicitly listed as rejected with a reason

Anti-patterns to avoid

• Proposing ADRs for routine choices already covered by coding standards or existing ADRs
• Vague titles that do not describe a specific decision
• Proposing too many ADRs — if everything is consequential, nothing is
• Writing full ADR content instead of identifying and prioritising decisions
• Ignoring existing ADRs that already address the topic

Output

Save as {domain}/decisions/proposed-adrs.md using template.md as the scaffold. Once reviewed, each accepted item becomes an ADR-####-*.md file written with write-adr.