---

name: spec description: Build the pre-migration spec of a website — pages, redirects, 404s, layout variants, the EDS blocks each page needs with reuse verdicts, dynamic features, martech and open decisions — as documented knowledge files for people and a migration agent. Use when someone asks to scope, estimate or plan a migration, wants "which pages use block X / which blocks does page Y need", a redirect or 404 inventory, or the facts behind a migration brief. Not the migration itself (replica, migrate, rollout). license: Apache-2.0 compatibility: Requires Node 20+, and Playwright with Chromium resolvable from the project for the capture stages. Real-user data needs an AEM Operational Telemetry domain key.

stardust:spec — the migration spec, before the migration

The spec answers the people planning a migration (what to build, reuse, fix or decide) and the agent that runs it (archetypes, block backlog, contracts, redirects, a default for every decision). The agent builds it stage by stage.

Principles

• Evidence, then judgement. Stages S1–S6 and S8 measure the live site; S7 and S9 are judgement (mapping, reuse, features, questions) recorded in judgement/ with a rationale per decision.
• Blind judgement. Judge from the source site only (reference/judgement.md); state the provenance in implementation.json#provenance.
• Variants, not templates. CMS templates are loose; plan, capture and QA by layout variant (S8).
• Every open question ships a default. A hands-off migration applies it; a recorded answer replaces it.
• Computed, never typed. Every figure in findings, feature reach and question impact is a rule (reference/knowledge.md § Rules) the knowledge stage evaluates.

Setup

stardust/spec/spec.config.json (reference/config.md): origin, scopePath, template rule, parser profile (aem-classic, aem-core, or generic for any other site) + main selector, optional maxPages, rum, referenceBlocks. Copy the spec, diff, dynamics and deploy scripts to stardust/scripts/<skill>/ (the stages import them).

Stages

#	Stage	Command (from the project root)	Output
S1	Inventory	spec-inventory.mjs	<work>/inventory/
S2	Fetch	spec-fetch.mjs	<work>/fetch/
S3	Parse	spec-parse.mjs	<work>/parse/
S4	Links	spec-links.mjs, then spec-fetch.mjs --urls <work>/links/pages.txt --out <work>/links/pages.jsonl and spec-parse.mjs --fetch <work>/links/pages.jsonl --out <work>/links	<work>/links/
S5	Real-user data (optional)	spec-rum.mjs (key from $RUM_DOMAIN_KEY)	<work>/rum/rum.json
S6	First capture	spec-pick.mjs --components-only, spec-capture.mjs	<work>/media/
S7	Judgement: mapping	spec-profile.mjs, spec-sheet.mjs <component>, write judgement/mapping.json, spec-map.mjs	<work>/map/page-blocks.jsonl
S8	Variants + visuals	spec-variants.mjs, spec-pick.mjs, spec-capture.mjs	<work>/map/variants.json, <work>/media/
S9	Implementation	dynamics-detect.mjs --urls <reps> --out <work>/dynamics, spec-martech.mjs, chrome-explore.mjs <home> <work>/chrome/header.json; write judgement/catalog.json, implementation.json, findings.json, search-probes.json	<work>/, judgement/
S10	Knowledge	spec-knowledge.mjs	knowledge/

Each stage logs start and end to stardust/status.jsonl (ledger.mjs spec s1-inventory start). <work> is stardust/.work/spec/, never committed. Large sites: S2 runs at 4 parallel requests and is resumable — start it, then write config and judgement scaffolding while it runs. One browser job at a time (S6/S8/S9), two tabs.

Judgement (S7, S9)

Start from templates/. mapping.json and catalog.json: reference/judgement.md. implementation.json: reference/implementation.md. findings.json: 6–10 plain-text { title, text, chapter, rank } headlines. Recorded answers go in judgement/answers.json.

Outputs

judgement/ and knowledge/ in stardust/spec/, committed; reference/knowledge.md is the contract. Raw material, captures and crops stay in <work>.

Gates

• S7 passes when spec-map.mjs reports no unmapped component and every block in the page blocks is in catalog.json (spec-knowledge.mjs warns otherwise).
• S10 passes when spec-knowledge.mjs exits 0 (every rule computed) and every open question has a default.
• A blocked origin (S1 or S2 exit 3: bot challenges or refusals on 10% or more) stops the build: ask the user to allow-list the crawler, or to choose --headed (the plugin's stealth real-Chrome tier from the diff skill's live-session.mjs, as replica uses) or --archive <date> (Internet Archive captures, which the provenance and a finding must disclose). Never choose for them, and never work around a block another way.
• Before sharing: no customer secret, internal evaluation or other migration's name in the project or the output.

References

• reference/config.md — spec.config.json, template rules, parser profiles.
• reference/judgement.md — the blind rule, mapping rules, contact sheets, block families, reuse verdicts.
• reference/implementation.md — features, martech, data layer, metadata, indexes, locales, open questions.
• reference/knowledge.md — the output contract: files, fields, the rule format.
• reference/evaluation.md — scoring a spec against a delivered migration; blind re-judgement.