Draft capability entry (reuse-surface REUSE-WP-0017-T04, cohort 1)

Honest first-pass maturity vector grounded in README/docs/tests present
in this repo; no invented evidence. Flagged for human review before
publish. See reuse-surface history/2026-07-06-coverage-classification.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

registry/capabilities/capability.infotech.citation-engine.md

@@ -0,0 +1,119 @@
+---
+id: capability.infotech.citation-engine
+name: Citation Evidence Domain Engine
+summary: Core domain model and engine services for the citation-evidence ecosystem — shared vocabulary,
+  in-memory repositories, orchestration services, event bus, and citation card renderers.
+owner: citation-engine
+status: draft
+domain: infotech
+tags:
+- citation
+- evidence
+- domain-model
+maturity:
+  discovery:
+    current: D3
+    target: D5
+    confidence: medium
+    rationale: README documents the domain vocabulary (Document, Selector, Annotation, EvidenceItem/Link/Set)
+      and points to wiki/SharedContracts.md as the authoritative conformance copy shared with citation-evidence.
+  availability:
+    current: A1
+    target: A3
+    confidence: medium
+    rationale: Published as `@citation-evidence/engine`, consumed today only as a local sibling-checkout
+      package link; no registry publish yet.
+external_evidence:
+  completeness:
+    level: C1
+    confidence: low
+    basis: scope_vs_intent_and_consumer_expectations
+    satisfied_expectations:
+    - shared vocabulary and branded IDs
+    - in-memory repositories and orchestration services
+    - citation card renderers
+    broken_expectations: []
+    out_of_scope_expectations: []
+  reliability:
+    level: R0
+    confidence: low
+    basis: consumer_quality_signals
+    known_reliability_risks:
+    - only consumed by sibling citation-evidence today; no independent external consumer
+discovery:
+  intent: Provide the shared domain model and engine services underlying the citation-evidence workspace,
+    decoupled from any single UI shell.
+  includes:
+  - Document/Selector/Annotation/EvidenceItem/EvidenceLink/EvidenceSet types
+  - in-memory repositories, event bus, orchestration services
+  - citation card rendering
+  excludes:
+  - the evidence-workspace UI shell (owned by citation-evidence)
+  assumptions: []
+  use_cases: []
+  research_memos: []
+availability:
+  current_level: A1
+  target_level: A3
+  current_artifacts:
+  - '`@citation-evidence/engine` npm package (local link, not published)'
+  target_artifacts: []
+  consumption_modes:
+  - library import (workspace link)
+relations:
+  depends_on: []
+  supports: []
+  related_to: []
+evidence:
+  documentation:
+  - README.md
+  - wiki/SharedContracts.md
+  tests:
+  - vitest.config.ts
+  consumer_feedback: []
+  bug_reports: []
+  incidents: []
+consumer_guidance:
+  recommended_for:
+  - citation-evidence and future citation-domain consumers within the same monorepo/workspace
+  not_recommended_for:
+  - consumers outside the citation-evidence workspace (package not published to a registry)
+  known_limitations:
+  - not yet published; only consumable via sibling-checkout workspace link
+promotion_history: []
+---
+
+# Citation Evidence Domain Engine
+
+## Overview
+
+`citation-engine` is the extracted domain model and engine layer for the citation-evidence ecosystem, published (workspace-local) as `@citation-evidence/engine` and consumed by the citation-evidence umbrella app.
+
+## Assessment notes
+
+### Discovery
+
+README documents the domain vocabulary (Document, Selector, Annotation, EvidenceItem/Link/Set) and points to wiki/SharedContracts.md as the authoritative conformance copy shared with citation-evidence.
+
+### Availability
+
+Published as `@citation-evidence/engine`, consumed today only as a local sibling-checkout package link; no registry publish yet.
+
+### Completeness
+
+First-pass honest assessment from the REUSE-WP-0017 coverage campaign
+(reuse-surface). No external consumer feedback exists yet; levels reflect
+scope-vs-intent documentation quality, not internal code quality.
+
+### Reliability
+
+No production consumer telemetry exists yet; reliability level is
+intentionally conservative pending REUSE-WP-0019 reuse-telemetry evidence.
+
+## Promotion checklist
+
+- [x] ID follows `capability.<domain>.<name>` pattern
+- [x] Maturity enums match `specs/CapabilityMaturityStandard.md`
+- [x] `external_evidence` is populated separately from `maturity`
+- [ ] Relations reference valid capability IDs (none yet)
+- [x] Index entry added in `registry/indexes/capabilities.yaml`

registry/indexes/capabilities.yaml

@@ -1,4 +1,19 @@
 version: 1
-updated: '2026-06-16'
+updated: '2026-07-06'
 domain: helix_forge
-capabilities: []
+capabilities:
+- id: capability.infotech.citation-engine
+  name: Citation Evidence Domain Engine
+  summary: Core domain model and engine services for the citation-evidence ecosystem — shared vocabulary,
+    in-memory repositories, orchestration services, event bus, and citation card renderers.
+  vector: D3 / A1 / C1 / R0
+  domain: infotech
+  status: draft
+  owner: citation-engine
+  path: registry/capabilities/capability.infotech.citation-engine.md
+  tags:
+  - citation
+  - evidence
+  - domain-model
+  consumption_modes:
+  - library import (workspace link)