feat: add curved RectRing eaves with corner uplift

docs/BUILD_COVERAGE_MATRIX.md

@@ -68,6 +68,7 @@ Observed support diagnostics on the current samples:
 | `temple-palace-dome-study` | pass | pass | 58 | 828 | 0 | Assembly authoring works; dome diagnostics remain noisy |
 | `xi-an-bell-tower-study` | pass | pass | 20 | 108 | 728 | Good visual landmark probe; broad eaves create intentional span/cantilever review points |
 | `giant-wild-goose-pagoda-study` | pass | pass | 20 | 0 | 24 | Walkable pagoda is structurally connected; repeated levels are verbose and need authoring support |
+| `pagoda-eave-flare-study` | pass | pass | 20 | 0 | 0 | Multi-level pagoda with `RectRing` cornerRise eaves on default strict policy; overhang review warnings are expected and no decorative suppression is needed |
 | `ship-bow-shape` | pass | pass | 38 | 1996 | 0 | Ship bow taper is useful visually but support diagnostics need clearer intent |
 | `arcade-bracket-study` | pass | pass | 60 | 1328 | 0 | Arch/bracket sample exposes span semantics and diagnostic noise |
 

docs/COMPONENT_DESIGN_GUIDE.md

@@ -264,7 +264,7 @@ If an existing component plus clearer docs solves the problem, do not add a new
 - `SteppedTier`: horizontal stepped tiers
 - `VerticalSetbackVolume`: vertical setback segments
 - `SteppedDome`: bounded stepped dome approximation
-- `RectRing`: rectangular ring band (eaves, cornices, parapets) around an open interior
+- `RectRing`: rectangular ring band (eaves, cornices, parapets) around an open interior, with optional stepped `cornerRise` toward corners for curved-eave/corner-uplift silhouettes
 - `GableRoof`: pitched roof volume
 - `FlatRoof`: flat cover/cap/canopy
 

docs/COMPONENT_PLAN_SPEC.md

@@ -178,6 +178,8 @@ The expander translates semantic dependencies into low-level CraftDAG inputs and
 
 For attached and covering components, `placement.target` and `placement.over` are implicit dependencies. Agents may include them in `inputs` for readability, but the expander must add the low-level CraftDAG dependency even when they are omitted.
 
+When a dependency resolves to a multi-segment source component, the expander connects the consumer to every emitted segment instead of one canonical part: a `RectRing` with `cornerRise` bears through all of its `ring_<side>_seg<n>` nodes, so anything resting on a flared eave depends on the whole ring. Flat `RectRing`s keep the legacy single `ring_front` attachment.
+
 ## v0.1 Component Set
 
 Start with a small component vocabulary:
@@ -239,7 +241,9 @@ Use `VerticalSetbackVolume` for tall landmark massing with discrete setbacks, su
 
 Use `SteppedDome` for bounded Minecraft-style dome approximations, such as Taj-style central domes, temple or mosque roofs, observatories, rotundas, and fantasy tower caps. It expands into stacked shrinking tiers inside one anchored box. Use it when the authoring intent is a dome-like roof or cap; use `SteppedTier` for horizontal terraces and `VerticalSetbackVolume` for tall setback towers. Do not add landmark-specific dome component types.
 
-Use `RectRing` for rectangular ring bands around an open interior: eave bands on tiered towers and pagoda-style roofs, cornices, parapets, plinth bands, balcony fascias, and trim frames around courtyards or roof plates. It is the rectangular counterpart to `CircleRing` and expands into at most four axis-aligned band boxes (`ring_front`, `ring_back`, `ring_left`, `ring_right`) inside one anchored bounding box. Use `options.bandWidth` for the inward band thickness and `options.height` for the band height. The band must leave at least a one-block open interior; use `Platform` instead when the surface should be a full slab. Corner flares and curved profiles are intentionally out of scope; pair it with `SteppedDome` or `CircleRing` for curved caps.
+Use `RectRing` for rectangular ring bands around an open interior: eave bands on tiered towers and pagoda-style roofs, cornices, parapets, plinth bands, balcony fascias, and trim frames around courtyards or roof plates. It is the rectangular counterpart to `CircleRing` and expands into at most four axis-aligned band boxes (`ring_front`, `ring_back`, `ring_left`, `ring_right`) inside one anchored bounding box. Use `options.bandWidth` for the inward band thickness and `options.height` for the band height. The band must leave at least a one-block open interior; use `Platform` instead when the surface should be a full slab. Pair it with `SteppedDome` or `CircleRing` for curved caps.
+
+For stepped eave curvature, set `options.cornerRise` to a small non-negative integer: each corner column gains up to that many extra blocks above `options.height`, stepping down over `options.riseSpan` columns (defaults to `cornerRise`, one block per step) toward the middle of each edge. This approximates curved eave edges and corner uplift with deterministic integer segments named `ring_<side>_seg<n>`; keep the ring's inner hole aligned with the tower cross-section at that height so the band bears on the walls. The placement must declare vertical room (`options.height + options.cornerRise <= placement.size.height`) or validation rejects the plan. Flat rings without `cornerRise` expand exactly as before. Components that consume a cornerRise ring through `inputs` are connected to every emitted segment, preserving whole-ring bearing in the expanded graph.
 
 Use `RailingRun` for repeated posts plus horizontal rails along bridges, decks, walls, balconies, and platforms. It is a bounded run, not a fence/pathfinding simulator. Use `postSpacing`, `includeTopRail`, and `includeMidRail` for controlled detail.
 
@@ -690,6 +694,7 @@ The analyzer reports:
 - `DISCONNECTED_COMPONENT`: blocks are not connected to configured support roots.
 - `FLOATING_SOURCE_NODE`: a source node contributes disconnected blocks.
 - `LARGE_CANTILEVER`: connected blocks exceed the configured `maxCantilever` distance from nearby vertical support.
+- `MINIMAL_ATTACHMENT`: a component that declares `inputs` and uses `must_connect_to_input` or `must_connect_to_ground` connects to the rest of the build through fewer than `minAttachmentContacts` (default 2) shared faces, such as an eave ring resting on a single corner block.
 - `NOT_VERTICALLY_SUPPORTED_BUT_CONNECTED`: blocks have air below but remain connected through adjacent blocks, such as bridge spans or rails.
 - `ALLOWED_*`: the same condition is allowed by `structural.supportPolicy` when `includeAllowed: true`.
 
@@ -719,9 +724,11 @@ The result includes a `summary` field for agent and product quality gates:
 Quality gate status is conservative:
 
 - `block`: at least one unallowed `DISCONNECTED_COMPONENT` or `FLOATING_SOURCE_NODE`.
-- `review`: no blocking diagnostics, but at least one `LARGE_CANTILEVER` or `NOT_VERTICALLY_SUPPORTED_BUT_CONNECTED`.
+- `review`: no blocking diagnostics, but at least one `LARGE_CANTILEVER`, `MINIMAL_ATTACHMENT`, or `NOT_VERTICALLY_SUPPORTED_BUT_CONNECTED`.
 - `pass`: no blocking or review diagnostics. Allowed diagnostics do not downgrade the status.
 
+Components without declared `inputs`, and components using `decorative` or `may_float` policies, are exempt from `MINIMAL_ATTACHMENT`; standalone foundations and intentional decorations stay quiet.
+
 The result also includes `sourceSummaries`, which aggregate total blocks, bounds, disconnected block counts, vertical unsupported counts, and large cantilever counts by `sourceNodeId`.
 
 By default, diagnostics for `decorative` and `may_float` components are filtered out. Use `includeAllowed: true` when a UI or repair loop wants to show allowed floating elements for inspection.

docs/LLM_AUTHORING_CONTRACT.md

@@ -120,7 +120,7 @@ Use `SteppedDome` for bounded Minecraft-style dome roofs and caps: Taj-style dom
 
 Use `RailingRun` for bounded posts and rails along decks, bridges, walls, and balconies. Prefer it over manually listing many posts. Use `postSpacing` for rhythm and `includeMidRail` for extra detail.
 
-Use `RectRing` for rectangular eave bands, cornices, parapets, plinth bands, and trim frames with an open interior. Set `options.bandWidth` for band thickness; keep at least a one-block open hole. Use `Platform` for full slabs and `CircleRing` for circular rings. Do not invent pagoda-eave or landmark-specific ring types.
+Use `RectRing` for rectangular eave bands, cornices, parapets, plinth bands, and trim frames with an open interior. Set `options.bandWidth` for band thickness; keep at least a one-block open hole. Use `Platform` for full slabs and `CircleRing` for circular rings. For pagoda/temple eaves, set `options.cornerRise` (1-3) with `options.riseSpan` (defaults to `cornerRise`) so the band steps upward toward each corner, approximating curved eave edges and corner uplift; size the ring so its inner hole matches the wall cross-section at that height, and give the placement enough height for base + rise. Do not invent pagoda-eave or landmark-specific ring types. Components that declare `inputs` on a cornerRise ring are automatically attached to every emitted segment, so no per-segment refs are needed.
 
 Use `ArcadeRun` for repeated stepped arch-like facade rhythms: colosseum bays, gothic arcades, palace cloisters, bridge arches, and monumental walls. Do not try to describe exact curves; use Minecraft-like blocky arches.
 
@@ -455,7 +455,7 @@ Agents should use structured diagnostics when available. Prefer `diagnosticsFrom
 
 For support warnings after successful compilation, use `analyzeComponentPlanSupport(plan)`. For preview/export tools that already have compiled voxels, use `analyzeVoxelSupport(voxelPlan)`.
 
-Support diagnostics are warnings, not validation failures. Repair unexpected `DISCONNECTED_COMPONENT` or `FLOATING_SOURCE_NODE` warnings by adding foundations, posts, brackets, shelves connected to inputs, or by moving the component onto a supporting surface. Treat `NOT_VERTICALLY_SUPPORTED_BUT_CONNECTED` as a review signal for bridges, roofs, rails, and spans. Treat `LARGE_CANTILEVER` as a stronger span warning: add nearby posts, arches, cables, brackets, or explicit structural intent.
+Support diagnostics are warnings, not validation failures. Repair unexpected `DISCONNECTED_COMPONENT` or `FLOATING_SOURCE_NODE` warnings by adding foundations, posts, brackets, shelves connected to inputs, or by moving the component onto a supporting surface. Treat `NOT_VERTICALLY_SUPPORTED_BUT_CONNECTED` as a review signal for bridges, roofs, rails, and spans. Treat `LARGE_CANTILEVER` as a stronger span warning: add nearby posts, arches, cables, brackets, or explicit structural intent. Treat `MINIMAL_ATTACHMENT` as a roof-frame review signal: a component you connected with `inputs` rests on very few shared faces; widen the bearing surface or add brackets instead of silencing it with `decorative`.
 
 Use `sourceSummaries` to identify the noisiest source nodes before editing. Prefer repairing the largest unexpected source groups first instead of making broad random changes.
 

examples/component-plans/pagoda-eave-flare-study.componentplan.json

@@ -0,0 +1,149 @@
+{
+  "version": "0.1",
+  "name": "Pagoda Eave Flare Study",
+  "grid": {
+    "unitBlocks": 1
+  },
+  "policy": {
+    "sizeTier": "large"
+  },
+  "bounds": {
+    "width": 40,
+    "height": 44,
+    "length": 40
+  },
+  "palette": {
+    "foundation": "minecraft:stone_bricks",
+    "wall": "minecraft:sandstone",
+    "floor": "minecraft:cut_sandstone",
+    "roof": "minecraft:cyan_terracotta",
+    "trim": "minecraft:gold_block"
+  },
+  "components": [
+    {
+      "id": "plinth",
+      "type": "Foundation",
+      "role": "temple_plinth",
+      "placement": {
+        "anchor": { "x": 4, "y": 0, "z": 4 },
+        "size": { "width": 32, "height": 1, "length": 32 }
+      }
+    },
+    {
+      "id": "podium",
+      "type": "SteppedTier",
+      "role": "tiered_temple_podium",
+      "inputs": [{ "ref": "plinth" }],
+      "placement": {
+        "anchor": { "x": 8, "y": 1, "z": 8 },
+        "size": { "width": 24, "height": 4, "length": 24 }
+      },
+      "options": {
+        "axis": "both",
+        "levels": 2,
+        "stepHeight": 2,
+        "insetPerLevel": 1
+      }
+    },
+    {
+      "id": "pagoda_body",
+      "type": "FloorStack",
+      "role": "multi_level_pagoda_levels",
+      "inputs": [{ "ref": "podium" }],
+      "placement": {
+        "anchor": { "x": 10, "y": 5, "z": 10 },
+        "size": { "width": 20, "height": 30, "length": 20 }
+      },
+      "options": {
+        "levels": 5,
+        "levelHeight": 6,
+        "setbackPerLevel": 1,
+        "stairStyle": "ladder",
+        "includeDoorways": true,
+        "includeWindows": true
+      }
+    },
+    {
+      "id": "eave_1",
+      "type": "RectRing",
+      "role": "flared_eave_level_1",
+      "inputs": [{ "ref": "pagoda_body" }],
+      "placement": {
+        "anchor": { "x": 8, "y": 10, "z": 8 },
+        "size": { "width": 24, "height": 4, "length": 24 }
+      },
+      "options": {
+        "bandWidth": 2,
+        "height": 1,
+        "cornerRise": 2,
+        "riseSpan": 3
+      }
+    },
+    {
+      "id": "eave_2",
+      "type": "RectRing",
+      "role": "flared_eave_level_2",
+      "inputs": [{ "ref": "pagoda_body" }],
+      "placement": {
+        "anchor": { "x": 9, "y": 16, "z": 9 },
+        "size": { "width": 22, "height": 4, "length": 22 }
+      },
+      "options": {
+        "bandWidth": 2,
+        "height": 1,
+        "cornerRise": 2,
+        "riseSpan": 3
+      }
+    },
+    {
+      "id": "eave_3",
+      "type": "RectRing",
+      "role": "flared_eave_level_3",
+      "inputs": [{ "ref": "pagoda_body" }],
+      "placement": {
+        "anchor": { "x": 10, "y": 22, "z": 10 },
+        "size": { "width": 20, "height": 4, "length": 20 }
+      },
+      "options": {
+        "bandWidth": 2,
+        "height": 1,
+        "cornerRise": 3,
+        "riseSpan": 3
+      }
+    },
+    {
+      "id": "roof_cap",
+      "type": "SteppedDome",
+      "role": "pagoda_roof_cap",
+      "inputs": [{ "ref": "pagoda_body" }],
+      "placement": {
+        "anchor": { "x": 13, "y": 35, "z": 13 },
+        "size": { "width": 14, "height": 6, "length": 14 }
+      },
+      "materials": {
+        "main": "roof"
+      },
+      "options": {
+        "levels": 3,
+        "insetPerLevel": 2,
+        "hollow": false
+      }
+    },
+    {
+      "id": "roof_finial",
+      "type": "SupportPost",
+      "role": "pagoda_roof_finial",
+      "inputs": [{ "ref": "roof_cap" }],
+      "placement": {
+        "anchor": { "x": 19, "y": 41, "z": 19 },
+        "size": { "width": 2, "height": 3, "length": 2 }
+      },
+      "materials": {
+        "main": "trim"
+      },
+      "structural": {
+        "supportPolicy": "decorative"
+      }
+    }
+  ]
+}