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+# Epic 10: NL-Assisted Catalog Discovery — Dependency Fishbone
+
+```mermaid
+---
+title: "E10 Fishbone: Dependency Flow"
+---
+graph LR
+    %% ── Spine: the goal ──────────────────────────────────
+    GOAL{{"E10\nNL-Assisted\nCatalog Discovery"}}
+
+    %% ── Phase 0: Foundation ──────────────────────────────
+    subgraph P0["Phase 0 — Foundation"]
+        direction TB
+        B180(["#180 Platform Registry ✅"])
+        B181(["#181 LinkML Schema Update"])
+        B180 --> B181
+    end
+
+    %% ── Phase 1: Import Pipeline ─────────────────────────
+    subgraph P1["Phase 1 — Import Pipeline"]
+        direction TB
+        B182(["#182 Import Handler Warnings"])
+        B183(["#183 Save-time Registry Resolution"])
+        B184(["#184 Nuke + Regenerate Catalog"])
+        B182 --> B184
+        B183 --> B184
+    end
+
+    %% ── Phase 2: CQL2 Extension ─────────────────────────
+    subgraph P2["Phase 2 — CQL2 Extension"]
+        direction TB
+        B185(["#185 CQL2 array_filter Evaluator"])
+        B186(["#186 Filter Bar Platform Chips"])
+        B185 --> B186
+    end
+
+    %% ── Phase 3: NL → CQL2 ──────────────────────────────
+    subgraph P3["Phase 3 — NL → CQL2"]
+        direction TB
+        B187(["#187 Build-time Enum Extraction"])
+        B188(["#188 NL → CQL2 Prompt Design"])
+        B189(["#189 LLM Transport Integration"])
+        B187 --> B188
+        B188 --> B189
+    end
+
+    %% ── Phase 4: Stakeholder Demo ────────────────────────
+    subgraph P4["Phase 4 — Stakeholder Demo"]
+        direction TB
+        B190(["#190 Prototype Demo UI"])
+    end
+
+    %% ── Cross-phase dependencies (the "bones") ──────────
+    B180 --> B182
+    B180 --> B183
+    B181 --> B183
+    B181 --> B185
+    B180 --> B187
+    B184 --> B187
+    B185 --> B188
+    B186 --> B190
+    B189 --> B190
+
+    %% ── Converge on goal ─────────────────────────────────
+    P4 --> GOAL
+
+    %% ── External dependencies (upstream — all complete) ──
+    subgraph EXT["External Dependencies (all complete)"]
+        direction TB
+        E126(["#126 CQL2 Filter Engine ✅"])
+        E127(["#127 Filter Bar Lozenge UI ✅"])
+        E125(["#125 STAC Extension Mock Data ✅"])
+    end
+
+    E126 -.->|"extended by"| B185
+    E127 -.->|"extended by"| B186
+    E125 -.->|"affected by"| B184
+
+    %% ── Styling ─────────────────────────────────────────
+    classDef complete fill:#4caf50,stroke:#2e7d32,color:#fff
+    classDef proposed fill:#42a5f5,stroke:#1565c0,color:#fff
+    classDef external fill:#4caf50,stroke:#2e7d32,color:#fff,stroke-dasharray: 5 5
+    classDef goal fill:#ab47bc,stroke:#6a1b9a,color:#fff
+
+    class B180 complete
+    class B181,B182,B183,B184,B185,B186,B187,B188,B189,B190 proposed
+    class E126,E127,E125 external
+    class GOAL goal
+```
+
+## Dependency Summary
+
+| Item | Depends On | Depended On By | Phase |
+|------|-----------|----------------|-------|
+| **#180** Platform Registry | — | #181, #182, #183, #187 | 0 |
+| **#181** LinkML Schema Update | #180 | #183, #185 | 0 |
+| **#182** Import Handler Warnings | #180 | #184 | 1 |
+| **#183** Save-time Registry Resolution | #180, #181 | #184 | 1 |
+| **#184** Nuke + Regenerate Catalog | #182, #183 | #187 | 1 |
+| **#185** CQL2 `array_filter` Evaluator | #181 | #186, #188 | 2 |
+| **#186** Filter Bar Platform Chips | #185 | #190 | 2 |
+| **#187** Build-time Enum Extraction | #180, #184 | #188 | 3 |
+| **#188** NL → CQL2 Prompt Design | #185, #187 | #189 | 3 |
+| **#189** LLM Transport Integration | #188 | #190 | 3 |
+| **#190** Stakeholder Demo UI | #186, #189 | — | 4 |
+
+## Critical Path
+
+**#180** → **#181** → **#183** → **#184** → **#187** → **#188** → **#189** → **#190**
+
+This 8-item chain determines the minimum elapsed time. The critical path runs through Foundation → Import Pipeline → NL → CQL2 → Demo.
+
+## Parallel Work Opportunities
+
+- **#182** (Import Warnings) can start as soon as #180 is done (already complete)
+- **#185** (CQL2 array_filter) can start as soon as #181 is done, independently of the Import Pipeline
+- **#186** (Filter Bar Chips) and **#187** (Enum Extraction) can run in parallel once their respective prerequisites are met
+
+## Legend
+
+- 🟢 **Green (solid)** — Complete (E10 items)
+- 🟢 **Green (dashed)** — Complete (external dependencies)
+- 🔵 **Blue** — Proposed (not yet started)
+- 🟣 **Purple** — Epic goal