Draft capability entry (reuse-surface REUSE-WP-0017-T04, cohort 3)

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.graph.nbgm-spec.md

@@ -0,0 +1,117 @@
+---
+id: capability.graph.nbgm-spec
+name: Network-Based Graph Model (NBGM) Specification
+summary: Generic system and versioned protocol specification for exploring dependency structures as network-based
+  graph models (NBGM), unifying entity/relationship inspection and reasoning across arbitrary domains.
+owner: vantage-point
+status: draft
+domain: infotech
+tags:
+- graph
+- nbgm
+- specification
+maturity:
+  discovery:
+    current: D2
+    target: D4
+    confidence: medium
+    rationale: SCOPE.md documents the core idea clearly (unifying entity/relationship inspection across
+      domains); note README.md is a stale repo-seed template leftover — SCOPE.md is authoritative. A substantial
+      draft protocol spec (nbgm-spec-v0.1.md, per docs/) exists.
+  availability:
+    current: A0
+    target: A2
+    confidence: medium
+    rationale: Specification-stage only; no implementation code found in this sweep (docs/ and registry/
+      and workplans/ only, no src/ or package manifest).
+external_evidence:
+  completeness:
+    level: C1
+    confidence: low
+    basis: scope_vs_intent_and_consumer_expectations
+    satisfied_expectations:
+    - a versioned protocol spec (docs/nbgm-spec-v0.1.md) exists
+    broken_expectations: []
+    out_of_scope_expectations: []
+  reliability:
+    level: R0
+    confidence: low
+    basis: consumer_quality_signals
+    known_reliability_risks:
+    - no implementation yet; availability is honestly A0 pending an actual reference implementation
+discovery:
+  intent: Define a generic, versioned protocol for exploring dependency structures as network-based graph
+    models, applicable across arbitrary domains, not tied to one specific graph engine.
+  includes:
+  - NBGM protocol specification (versioned)
+  - entity/relationship inspection and reasoning model
+  excludes:
+  - a reference implementation (not yet built)
+  assumptions: []
+  use_cases: []
+  research_memos: []
+availability:
+  current_level: A0
+  target_level: A2
+  current_artifacts:
+  - docs/nbgm-spec-v0.1.md
+  target_artifacts: []
+  consumption_modes:
+  - informational (specification only)
+relations:
+  depends_on: []
+  supports: []
+  related_to: []
+evidence:
+  documentation:
+  - SCOPE.md
+  - docs/nbgm-spec-v0.1.md
+  tests: []
+  consumer_feedback: []
+  bug_reports: []
+  incidents: []
+consumer_guidance:
+  recommended_for:
+  - repos designing a graph-based dependency/entity model wanting to align with a shared, versioned protocol
+    before building their own
+  not_recommended_for:
+  - needs for a working graph implementation today (specification only, no code yet)
+  known_limitations:
+  - specification-stage only; no reference implementation exists yet
+promotion_history: []
+---
+
+# Network-Based Graph Model (NBGM) Specification
+
+## Overview
+
+`vantage-point` defines the Network-Based Graph Model (NBGM): a generic, versioned protocol for exploring dependency structures as graph models, unifying entity/relationship inspection and reasoning across arbitrary domains. It is specification-stage only — a real, versioned spec document exists, but no reference implementation has been built yet.
+
+## Assessment notes
+
+### Discovery
+
+SCOPE.md documents the core idea clearly (unifying entity/relationship inspection across domains); note README.md is a stale repo-seed template leftover — SCOPE.md is authoritative. A substantial draft protocol spec (nbgm-spec-v0.1.md, per docs/) exists.
+
+### Availability
+
+Specification-stage only; no implementation code found in this sweep (docs/ and registry/ and workplans/ only, no src/ or package manifest).
+
+### 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`