refactor(M03): extract M2 prototype cache state

docs/modules/README.md

@@ -27,6 +27,7 @@
 | M2 mesh resource extractor | Implemented extraction | [`m2-mesh-resource-extractor.md`](m2-mesh-resource-extractor.md) |
 | M2 runtime mesh finalizer | Implemented extraction | [`m2-runtime-mesh-finalizer.md`](m2-runtime-mesh-finalizer.md) |
 | M2 raw model repository | Implemented extraction | [`m2-raw-model-repository.md`](m2-raw-model-repository.md) |
+| M2 prototype cache state | Implemented extraction | [`m2-prototype-cache-state.md`](m2-prototype-cache-state.md) |
 | WMO placement resolver | Implemented extraction | [`wmo-placement-resolver.md`](wmo-placement-resolver.md) |
 | WMO placement registry | Implemented extraction | [`wmo-placement-registry.md`](wmo-placement-registry.md) |
 | WMO render build step planner | Implemented extraction | [`wmo-render-build-step-planner.md`](wmo-render-build-step-planner.md) |

docs/modules/m2-mesh-load-pipeline-state.md

@@ -38,7 +38,7 @@ flowchart LR
     State --> FIFO[Finalize FIFO]
     FIFO --> Loader
     Loader --> Budget[M2_MESH_FINALIZE permit]
-    Loader --> Cache[M2 Mesh resource cache or shared missing cache]
+    Loader --> Cache[M2 Mesh resource cache or M2 prototype outcome state]
 ```
 
 Allowed dependencies are value containers, Strings and opaque integer statuses.
@@ -88,7 +88,7 @@ flowchart TD
     Permit -->|yes| Pop[Pop oldest terminal record]
     Pop --> Finalize[Loader gets Resource and delegates first-Mesh extraction]
     Finalize --> Prepare[M2RuntimeMeshFinalizer prepares Mesh]
-    Prepare --> Adopt[Loader adopts Mesh/missing state]
+    Prepare --> Adopt[Loader adopts Mesh or marks prototype outcome state]
 ```
 
 ## Lifecycle/state
@@ -137,7 +137,7 @@ flowchart TB
     Loader[StreamingWorldLoader] --> State[M2MeshLoadPipelineState]
     Loader --> Resource[ResourceLoader]
     Loader --> Budget[RenderBudgetScheduler]
-    Loader --> MeshCache[M2 Mesh resource cache and shared missing cache]
+    Loader --> MeshCache[M2 Mesh resource and prototype outcome cache states]
     Loader --> Finalizer[M2RuntimeMeshFinalizer]
     State -. no dependency .-> Resource
     State -. no dependency .-> Budget
@@ -151,7 +151,8 @@ flowchart TB
 - Loader owns ResourceLoader request lifetime and drains active paths before shutdown clear.
 - `M2MeshResourceCacheState` owns prepared static Mesh references and
   `M2RuntimeMeshFinalizer` owns refresh/rebuild/fallback. The loader owns shared
-  missing state, raw I/O and remaining engine resources.
+  adoption decisions, raw I/O and remaining engine resources; the prototype
+  cache service owns missing outcomes.
 - Snapshot and diagnostic records are detached; caller mutation cannot affect state.
 
 ## Errors, cancellation and recovery
@@ -226,7 +227,8 @@ rebuild policy are unchanged; no migration or rebake is required.
 | `src/render/m2/m2_mesh_resource_cache_state.gd` | Prepared static Mesh references and final clear |
 | `src/render/m2/m2_mesh_resource_extractor.gd` | First-Mesh selection and temporary PackedScene lifetime |
 | `src/render/m2/m2_runtime_mesh_finalizer.gd` | Refresh/rebuild/fallback preparation |
-| `src/scenes/streaming/streaming_world_loader.gd` | Cache path choice, I/O polling, permits and Mesh/missing adoption |
+| `src/render/m2/m2_prototype_cache_state.gd` | Missing-model outcome retention |
+| `src/scenes/streaming/streaming_world_loader.gd` | Cache path choice, I/O polling, permits and adoption decisions |
 | `src/render/m2/m2_runtime_mesh_rebuild_classifier.gd` | Downstream stale Mesh rebuild decision |
 | `src/tools/verify_m2_mesh_load_pipeline_state.gd` | Lifecycle/boundary/timing regression |
 

docs/modules/m2-mesh-resource-cache-state.md

@@ -71,13 +71,13 @@ Store and clear mutate only the cache Dictionary and Resource reference counts.
 flowchart TD
     Lookup[Lookup normalized M2 path] --> Cached{Mesh cached?}
     Cached -->|yes| Return[Return retained Mesh]
-    Cached -->|no| Missing{Shared missing state?}
+    Cached -->|no| Missing{Prototype outcome says missing?}
     Missing -->|yes| Null[Return null]
     Missing -->|no| Load[Loader request or synchronous fallback]
     Load --> Prepare[Extractor and runtime finalizer prepare Mesh]
     Prepare --> Valid{Prepared Mesh valid?}
     Valid -->|yes| Store[Store or replace cache entry]
-    Valid -->|no| MarkMissing[Loader updates shared missing state]
+    Valid -->|no| MarkMissing[Loader updates prototype outcome state]
     Store --> Return
 ```
 
@@ -131,7 +131,8 @@ flowchart TB
 - The cache owns normalized-path Strings and strong Mesh references.
 - Borrowed Mesh lookups do not transfer ownership or duplicate resources.
 - `M2MeshResourceExtractor` owns first-Mesh selection and temporary PackedScene
-  instances. The loader owns missing/prototype/animated state and MultiMeshes.
+  instances. `M2PrototypeCacheState` owns missing/prototype/animated state; the
+  loader owns MultiMeshes and adoption decisions.
 - The loader drains asynchronous work before the final cache clear.
 
 ## Errors, cancellation and recovery
@@ -190,8 +191,7 @@ the historical Mesh cache had no queue contribution or log site.
 ## Known gaps and risks
 
 - Strong Mesh references intentionally remain until final shutdown.
-- Shared missing state cannot move here without also redesigning prototype and
-  animated lookup behavior.
+- Missing/prototype/animated lookup state is now a separate sibling service.
 - No proprietary M2 traversal, leak/descriptor-pressure, p95/p99 or paired
   original-client capture is included.
 
@@ -201,7 +201,8 @@ the historical Mesh cache had no queue contribution or log site.
 |---|---|
 | `src/render/m2/m2_mesh_resource_cache_state.gd` | Prepared Mesh references and final clear |
 | `src/render/m2/m2_mesh_resource_extractor.gd` | First-Mesh selection and temporary PackedScene lifetime |
-| `src/scenes/streaming/streaming_world_loader.gd` | Normalization, raw/resource I/O, missing state and materialization |
+| `src/render/m2/m2_prototype_cache_state.gd` | Prototype references and negative lookup outcomes |
+| `src/scenes/streaming/streaming_world_loader.gd` | Normalization, raw/resource I/O and materialization |
 | `src/render/m2/m2_runtime_mesh_finalizer.gd` | Refresh/rebuild/fallback preparation |
 | `src/render/m2/m2_mesh_load_pipeline_state.gd` | Pending request and terminal finalize records |
 | `src/tools/verify_m2_mesh_resource_cache_state.gd` | Cache ownership/lifetime/boundary/timing regression |

docs/modules/m2-mesh-resource-extractor.md

@@ -194,7 +194,8 @@ normalized M2 path. Its verifier measures traversal time and temporary Node coun
 | Path | Responsibility |
 |---|---|
 | `src/render/m2/m2_mesh_resource_extractor.gd` | First-Mesh traversal and temporary PackedScene lifetime |
-| `src/scenes/streaming/streaming_world_loader.gd` | ResourceLoader/raw I/O, caching, missing state and materialization |
+| `src/render/m2/m2_prototype_cache_state.gd` | Prototype and missing/static-only lookup state |
+| `src/scenes/streaming/streaming_world_loader.gd` | ResourceLoader/raw I/O, cache decisions and materialization |
 | `src/render/m2/m2_runtime_mesh_finalizer.gd` | Refresh/rebuild/fallback preparation |
 | `src/render/m2/m2_mesh_resource_cache_state.gd` | Prepared Mesh retention |
 | `src/tools/verify_m2_mesh_resource_extractor.gd` | Resource/order/lifetime/boundary/timing regression |

docs/modules/m2-prototype-cache-state.md

@@ -0,0 +1,247 @@
+# M2 Prototype Cache State
+
+## Metadata
+
+| Field | Value |
+|---|---|
+| Status | Implemented extraction |
+| Target/work package | M03 / `M03-RND-M2-PROTOTYPE-CACHE-001` |
+| Owners | Detached static/animated prototypes and missing/static-animation outcomes |
+| Last verified | Worktree `work/sindo-main-codex/m03-m2-prototype-cache`, 2026-07-17 |
+| Profiles/capabilities | Static, GLB animated and native animated M2 prototype reuse |
+
+## Purpose
+
+Own the four shutdown-lifetime M2 prototype lookup states previously stored in
+`StreamingWorldLoader`: static and animated `Node3D` references, missing model
+paths and paths whose animation fallback is static-only.
+
+## Non-goals
+
+- Normalize paths, choose cache files, call ResourceLoader or parse raw M2 data.
+- Build, repair or instantiate prototypes, Meshes, materials or MultiMeshes.
+- Own animation/Mesh request queues, permits or tile/build state.
+- Add eviction, persistence, retries, profile rules or format changes.
+
+## Context and boundaries
+
+```mermaid
+flowchart LR
+    Loader[StreamingWorldLoader] --> State[M2PrototypeCacheState]
+    Resource[ResourceLoader / raw builders] --> Loader
+    State --> Static[Static prototype Node3D]
+    State --> Animated[Animated prototype Node3D]
+    State --> Missing[Missing-model path set]
+    State --> StaticOnly[Static-animation path set]
+    Loader --> Instances[Duplicate/animated instance materialization]
+```
+
+The state may depend on `Node3D` lifetime APIs and value-only path containers.
+Filesystem/native/ResourceLoader APIs, builders, worker pools, render scheduling,
+Mesh traversal and other application layers are forbidden.
+
+## Public API
+
+| Symbol | Kind | Purpose | Thread/lifetime | Errors |
+|---|---|---|---|---|
+| `has_static_prototype(path)` | Query | Test for one valid retained static prototype | Renderer main thread; shutdown lifetime | Empty/invalid returns false |
+| `find_static_prototype(path)` | Query | Return exact retained static Node reference | Renderer main thread; borrowed | Empty/unknown/invalid returns null |
+| `adopt_static_prototype(path, prototype)` | Command/query | Retain first valid static prototype and return canonical reference | Renderer main thread; until shutdown | Invalid input returns null; later candidate released |
+| `has_animated_prototype(path)` | Query | Test for one valid retained animated prototype | Renderer main thread; shutdown lifetime | Empty/invalid returns false |
+| `find_animated_prototype(path)` | Query | Return exact retained animated Node reference | Renderer main thread; borrowed | Empty/unknown/invalid returns null |
+| `adopt_animated_prototype(path, prototype)` | Command/query | Retain first valid animated prototype and return canonical reference | Renderer main thread; until shutdown | Invalid input returns null; later candidate released |
+| `mark_model_missing(path)` / `is_model_missing(path)` | Command/query | Store/query a missing-model outcome | Renderer main thread; until shutdown | Empty mark rejected |
+| `mark_animation_static(path)` / `is_animation_static(path)` | Command/query | Store/query static-only animation outcome | Renderer main thread; until shutdown | Empty mark rejected |
+| `diagnostic_snapshot()` | Diagnostic query | Return detached sorted path arrays for all four states | Caller-owned result | Never exposes Nodes |
+| `clear_and_release()` | Lifecycle command | Release prototypes and clear all state | Final shutdown after async drain | Idempotent |
+
+## Inputs and outputs
+
+| Direction | Contract/data | Producer | Consumer | Ownership | Thread/lifetime |
+|---|---|---|---|---|---|
+| Input | Normalized non-empty M2 path | Loader normalization | Cache state | Copied String key | Shutdown lifetime |
+| Input | Detached static Node3D | Cached scene/raw builder adapter | Cache state | Adopted on success | Until final shutdown |
+| Input | Detached animated Node3D | GLB/native animation adapter | Cache state | Adopted on success | Until final shutdown |
+| Input | Missing/static-only outcome | Loader failure/fallback adapter | Cache state | Boolean set entry | Until final shutdown |
+| Output | Canonical prototype Node3D | Cache state | Loader instance/material adapter | Borrowed exact reference | One lookup/use |
+| Output | Detached path-only snapshot | Cache state | Tests/diagnostics | Fresh caller-owned arrays | One query |
+
+Side effects are strong Node retention, release of rejected duplicate candidates,
+final Node destruction/queueing and mutation of runtime-only path state.
+
+## Data flow
+
+```mermaid
+flowchart TD
+    Request[Normalized prototype request] --> Positive{Valid prototype cached?}
+    Positive -->|yes| Return[Return exact prototype]
+    Positive -->|no| Negative{Missing or static-only outcome?}
+    Negative -->|yes| Fallback[Return caller fallback]
+    Negative -->|no| Load[Loader performs existing I/O/build]
+    Load --> Success{Valid prototype?}
+    Success -->|yes| Adopt[Adopt first candidate]
+    Adopt --> Return
+    Success -->|no| Mark[Mark relevant negative outcome]
+    Mark --> Fallback
+```
+
+## Lifecycle/state
+
+```mermaid
+stateDiagram-v2
+    [*] --> Empty
+    Empty --> Positive: adopt static/animated prototype
+    Empty --> Negative: mark missing/static-only path
+    Positive --> Positive: lookup or same-reference adoption
+    Positive --> Positive: duplicate candidate released; first wins
+    Negative --> Negative: repeated mark/query
+    Positive --> Released: final shutdown
+    Negative --> Released: final shutdown
+    Released --> Released: repeated clear
+    Released --> [*]
+```
+
+Map refresh does not transition or clear this service. Final scene shutdown calls
+`clear_and_release` only after worker and ResourceLoader work is drained.
+
+## Main sequence
+
+```mermaid
+sequenceDiagram
+    participant Loader as StreamingWorldLoader
+    participant State as M2PrototypeCacheState
+    participant Source as ResourceLoader/raw builder
+    Loader->>State: find static/animated(path)
+    alt positive hit
+        State-->>Loader: exact retained Node3D
+    else negative hit
+        Loader->>State: is missing/static-only(path)
+        State-->>Loader: true; use historical fallback
+    else uncached
+        Loader->>Source: existing load/build operation
+        alt valid prototype
+            Loader->>State: adopt(path, prototype)
+            State-->>Loader: canonical Node3D
+        else failure
+            Loader->>State: mark missing/static-only(path)
+        end
+    end
+    Loader->>State: shutdown clear_and_release()
+    State-->>Loader: all paths empty; Nodes released
+```
+
+## Dependency diagram
+
+```mermaid
+flowchart TB
+    Loader[StreamingWorldLoader] --> State[M2PrototypeCacheState]
+    State --> Node3D
+    Loader --> Raw[M2RawModelRepository]
+    Loader --> ResourceLoader
+    Loader --> StaticBuilder[M2Builder]
+    Loader --> AnimatedBuilder[M2NativeAnimatedBuilder]
+    State -. no dependency .-> Raw
+    State -. no dependency .-> ResourceLoader
+    State -. no dependency .-> StaticBuilder
+    State -. no dependency .-> MeshCache[M2MeshResourceCacheState]
+```
+
+## Ownership, threading and resources
+
+- Renderer main-thread adapters serialize all operations.
+- The state owns strong references to adopted static and animated prototype Nodes.
+- A duplicate detached candidate is released immediately; the first valid Node
+  stays canonical for that path.
+- Lookups borrow exact Node references without transferring ownership.
+- Detached Nodes are synchronously `free()`d at shutdown. Defensive in-tree
+  Nodes use `queue_free()` to preserve SceneTree rules.
+- Negative entries own only copied normalized-path Strings.
+
+## Errors, cancellation and recovery
+
+| Failure/state | Detection | Behavior | Diagnostic | Recovery |
+|---|---|---|---|---|
+| Empty path/null/invalid Node | Admission guard | Reject/null/false | Dedicated verifier | Correct caller input |
+| Unknown positive lookup | Map miss | Return null | Path snapshot | Loader continues existing load/fallback |
+| Duplicate candidate | Occupied valid path | Release candidate; return first | Identity fixture | None required |
+| Model source/load failure | Loader result | Mark missing outcome | Existing fallback behavior | New loader session/source repair |
+| Animation unavailable/unsafe | Loader policy/result | Mark static-only outcome | Existing fallback behavior | New loader session/cache repair |
+| Shutdown | Loader lifecycle | Release positive and clear all state | Shutdown verifier | New loader begins empty |
+| Cancellation | Not owned | No state transition inside this service | N/A | Loader drains/cancels before shutdown clear |
+
+## Configuration and capabilities
+
+| Setting/capability | Default | Profile | Runtime mutable | Effect |
+|---|---|---|---|---|
+| Positive cache lifetime | Final loader shutdown | All | No | Reuses detached prototypes across map refresh |
+| Negative cache lifetime | Final loader shutdown | All | No | Preserves historical fallback suppression |
+| Eviction capacity | Unbounded historical behavior | All | No | No mid-session Node destruction |
+
+Animation enablement, candidate/allow/deny rules, cache paths and per-frame
+permits remain loader configuration.
+
+## Persistence, cache and migration
+
+This is runtime-only state and serializes nothing. `.tscn/.glb`, material refresh
+and native M2 formats are unchanged; no migration or rebake is introduced.
+
+## Diagnostics and observability
+
+- `diagnostic_snapshot` exposes four sorted path arrays without Node references.
+- Existing `M2_ANIM_CACHE` and native animation logs remain loader-owned.
+- Existing renderer queue metrics remain unchanged because these tables never
+  contributed work counts.
+- Normalized relative path remains the correlation key.
+
+## Verification
+
+- `verify_m2_prototype_cache_state.gd`: invalid admission, exact static/animated
+  identity, independent positive/negative states, first-wins duplicate release,
+  detached/in-tree shutdown ownership, idempotent clear, detached diagnostics,
+  loader source boundaries and 100-by-256 bounded path-state timing.
+- Runtime-cache shutdown regression verifies final release through the real loader.
+- Raw repository/finalizer/extractor/Mesh cache/pipeline/material/animation/M2
+  build regressions protect adjacent behavior.
+- Fidelity evidence is exact cache transition and lifetime extraction. No new
+  proprietary asset or original-client visual comparison is claimed.
+
+## Extension points
+
+Eviction or byte/count budgets require measured memory evidence and explicit
+prototype-user lifetime rules. Animation request-state extraction can consume
+this service without moving ResourceLoader or builder ownership into it.
+
+## Capability status
+
+| Capability | Status | Evidence | Gap/next step |
+|---|---|---|---|
+| Static prototype retention | Implemented extraction | Identity/source/shutdown verifier | Asset-backed traversal/leak run pending |
+| Animated prototype retention | Implemented extraction | Independent identity/shutdown verifier | Legal animated success fixture pending |
+| Missing/static-only outcomes | Implemented extraction | Independent negative-state verifier | Recovery still requires new loader session |
+| Bounded eviction | Historical unbounded behavior | Documented lifetime | Add only after memory profiling |
+
+## Known gaps and risks
+
+- Strong Node references intentionally live until final shutdown.
+- Negative outcomes do not retain reason codes and cannot be individually retried,
+  preserving historical behavior.
+- No proprietary long traversal, descriptor pressure, leak, p95/p99 or paired
+  original-client evidence is included.
+
+## Source map
+
+| Path | Responsibility |
+|---|---|
+| `src/render/m2/m2_prototype_cache_state.gd` | Positive Node ownership, negative path state and shutdown release |
+| `src/scenes/streaming/streaming_world_loader.gd` | Normalization, I/O/build/fallback decisions and cache adapters |
+| `src/tools/verify_m2_prototype_cache_state.gd` | Admission/identity/lifecycle/source/timing regression |
+| `src/tools/verify_render_runtime_cache_shutdown.gd` | Integrated final-shutdown release regression |
+
+## Related decisions and references
+
+- [`m2-raw-model-repository.md`](m2-raw-model-repository.md)
+- [`m2-mesh-resource-cache-state.md`](m2-mesh-resource-cache-state.md)
+- [`m2-mesh-load-pipeline-state.md`](m2-mesh-load-pipeline-state.md)
+- [`world-renderer.md`](world-renderer.md)
+- [`../../RENDER.md`](../../RENDER.md)
+- [`../../targets/roadmap/02-rendering-and-graphics.md`](../../targets/roadmap/02-rendering-and-graphics.md)

docs/modules/m2-raw-model-repository.md

@@ -55,7 +55,7 @@ renderer policy and other application layers are forbidden.
 | Input | Extracted `.m2` bytes | Local legal extraction | Native M2Loader | File-owned | Native call |
 | Output | Static raw M2 Dictionary | Native `load_m2` | Loader/finalizer/M2Builder | Fresh native result | One caller operation |
 | Output | Animated raw M2 Dictionary | Native `load_m2_animated` | Loader/animated builder | Fresh native result | One caller operation |
-| Output | Empty Dictionary | Repository guards | Loader fallback/missing state | Fresh value | One failed call |
+| Output | Empty Dictionary | Repository guards | Loader fallback and prototype outcome adapter | Fresh value | One failed call |
 
 Side effects are limited to file-existence inspection, synchronous native file
 parsing and creation of one temporary native loader instance per accepted call.
@@ -133,7 +133,8 @@ flowchart TB
 ## Ownership, threading and resources
 
 - The repository owns only call-local path, native instance and result values.
-- The loader owns path normalization, cache/fallback selection and adoption.
+- The loader owns path normalization and fallback selection;
+  `M2PrototypeCacheState` owns prototype/negative adoption.
 - Native `M2Loader` owns parsing behavior and returns a new Dictionary value.
 - Calls are synchronous on the caller's thread; current renderer callers use the
   main thread. The module starts no tasks and touches no SceneTree objects.
@@ -145,7 +146,7 @@ flowchart TB
 |---|---|---|---|---|
 | Empty normalized path | String guard | Return `{}` | Dedicated verifier | Correct caller normalization |
 | Native extension absent | `ClassDB.class_exists` | Return `{}` | Existing renderer fallback | Install/load extension and retry |
-| Extracted file absent | `FileAccess.file_exists` | Return `{}` | Loader adopts historical missing state | Restore extraction and clear caller state |
+| Extracted file absent | `FileAccess.file_exists` | Return `{}` | Prototype cache records historical missing state through loader | Restore extraction and start a new loader session |
 | Instance/method absent | Null/`has_method` guard | Return `{}` | Source contract verifier | Repair extension registration |
 | Parse/non-Dictionary result | Result type check | Return `{}` | Existing loader fallback | Repair asset/parser and retry |
 | Cancellation requested | Not supported inside synchronous native call | Call completes | None | Caller controls whether to start call |
@@ -210,7 +211,8 @@ measured work packages rather than expansion of this repository.
 | Path | Responsibility |
 |---|---|
 | `src/render/m2/m2_raw_model_repository.gd` | Stateless native class/file/method boundary |
-| `src/scenes/streaming/streaming_world_loader.gd` | Path normalization, fallback/cache state and result consumers |
+| `src/render/m2/m2_prototype_cache_state.gd` | Prototype and negative-result retention |
+| `src/scenes/streaming/streaming_world_loader.gd` | Path normalization, fallback decisions and result consumers |
 | `src/native/src/m2_loader.cpp` | Native static/animated parsing implementation |
 | `src/tools/verify_m2_raw_model_repository.gd` | Rejected-input/source/dependency/timing regression |
 

docs/modules/world-renderer.md

@@ -7,7 +7,7 @@
 | Status | Partial |
 | Target/work package | M00 baseline; `M01-RND-STREAMING-FOCUS-001`; `M01-QAR-SERVER-SPAWN-RENDERER-001`; M03 facade/planner/scheduler/internal-access/ground/environment/entity packages; M03 terrain packages; M03 M2 packages; M03 WMO placement package |
 | Owners | Renderer workstream / milestone integrator |
-| Last verified | Worktree `work/sindo-main-codex/m03-m2-raw-model-repository`, 2026-07-17 |
+| Last verified | Worktree `work/sindo-main-codex/m03-m2-prototype-cache`, 2026-07-17 |
 | Profiles/capabilities | `Performance`, `Balanced`, `High`, `Custom`; Blizzlike fidelity incomplete |
 
 ## Purpose
@@ -138,6 +138,7 @@ from externally reading/writing loader-private queue, task, cache and tile-state
 | `M2MeshResourceExtractor` | Internal M2 scene/resource service | Selects first Mesh from direct Resource, PackedScene or Node subtree | Renderer main thread; stateless except temporary instance | Invalid/no Mesh returns null; temporary PackedScene root freed |
 | `M2RuntimeMeshFinalizer` | Internal M2 preparation service | Owns refresh version, rebuild classification, M2Builder rebuild and fallback | Renderer main thread; decisions cached until reset | Null returns null; missing/failed rebuild marks and reuses original Mesh |
 | `M2RawModelRepository` | Internal M2 native repository | Reads static/animated raw Dictionaries through exact M2Loader methods | Synchronous; stateless | Invalid/unavailable/non-Dictionary result returns empty Dictionary |
+| `M2PrototypeCacheState` | Internal M2 prototype cache | Owns detached static/animated Nodes and missing/static-only outcomes | Renderer main thread; final shutdown | Invalid admission rejected; first valid prototype wins |
 | `WmoPlacementResolver.normalize_relative_path/resolve_unique_key/resolve_world_transform` | Internal pure WMO service | Resolves cache key, registry identity and world transform | Main/any thread; stateless | Missing UID uses tile/index fallback; transform fields use historical defaults |
 | `WmoPlacementRegistry.add_reference/release_reference/contains/active_count/diagnostic_snapshot/clear` | Internal WMO service | Owns placement-key to tile/global reference sets | Renderer main thread; map session | Empty/unknown/non-owner input is rejected without mutation |
 | `WmoRenderBuildStepPlanner.plan_step` | Internal pure WMO service | Selects one mesh-first lightweight render-group operation and next cursors | Main/any thread; stateless | Raw integer comparisons are preserved without clamping |
@@ -182,6 +183,7 @@ loader configuration remains transitional composition data, not a caller API.
 | Internal WMO scene cache | Normalized path, `.tscn` path and validated PackedScene | Loader / `WmoSceneResourceCacheState` | Loader lookup, request poll and scene instantiation | State-owned PackedScene/path references; detached request snapshots | Until transient/full clear |
 | Internal ADT water load | Tile key, ADT path, task ID and parsed Dictionary | Loader/worker / `AdtWaterLoadPipelineState` | Loader task start, budgeted drain and finalization | State-owned records; mutex result mailbox | Request through result completion/reset |
 | Internal raw M2 read | Extracted directory and normalized relative path | Loader / `M2RawModelRepository` | Finalizer, static or animated builder adapters | Fresh Dictionary; repository retains nothing | One synchronous native call |
+| Internal M2 prototype state | Normalized path, adopted static/animated Node or negative outcome | Loader / `M2PrototypeCacheState` | Loader reuse/fallback adapters | State-owned strong Node refs and Strings; detached diagnostics | Until final shutdown |
 | Output | Desired tile/detail operations | Streamer plan application | Finalize queues | Loader-owned | Cross-frame |
 | Output | Terrain/M2/WMO/liquid instances | Loader/builders | Godot world/renderer | Loader/world owner | Main-thread attach |
 | Output | Detached renderer metrics | `WorldRenderFacade` | Capture/baseline tools | Caller-owned deep copy | On demand |
@@ -377,10 +379,11 @@ sequenceDiagram
   finalizer. The raw repository loads value data; loader retains Mesh adoption.
 - `M2MeshLoadPipelineState` owns static M2 pending Resource paths, opaque
   terminal statuses and completion-order finalize FIFO. The loader retains cache
-  path selection, ResourceLoader calls, permits, shared missing state and adoption.
+  path selection, ResourceLoader calls, permits and adoption decisions; prototype
+  cache state owns shared missing outcomes.
 - `M2MeshResourceCacheState` owns prepared static Mesh references and releases
-  them at the existing final-shutdown site. The loader retains missing/prototype
-  state and materialization.
+  them at the existing final-shutdown site. Prototype state and materialization
+  belong to the sibling cache service and loader respectively.
 - `M2MeshResourceExtractor` owns depth-first first-Mesh selection and temporary
   PackedScene instance destruction. The loader retains ResourceLoader I/O,
   cache/missing adoption and materialization.
@@ -388,8 +391,12 @@ sequenceDiagram
   M2Builder rebuild and original-Mesh fallback. The loader loads raw data only
   after the finalizer reports that a cached Mesh is stale.
 - `M2RawModelRepository` owns FileAccess/ClassDB availability and the exact
-  `load_m2`/`load_m2_animated` calls. The loader retains normalization,
-  fallback order, missing/prototype state and every result consumer.
+  `load_m2`/`load_m2_animated` calls. The loader retains normalization, fallback
+  order and every result consumer; `M2PrototypeCacheState` retains outcomes.
+- `M2PrototypeCacheState` owns exact static/animated prototype references,
+  missing-model and static-animation path sets, duplicate-candidate release and
+  final-shutdown Node cleanup. ResourceLoader, builders and fallback decisions
+  remain loader-owned.
 - Rendered-ground query results and diagnostic snapshots are caller-owned values;
   the facade never returns Mesh, Node, tile-state or queue references.
 - Loaded-mesh ground sampling is renderer diagnostics, not authoritative gameplay
@@ -531,6 +538,7 @@ Exact exported settings and cache versions remain documented in [`../../RENDER.m
 | M2 placement transform resolver | Implemented extraction | Scene-free formula/source/timing contract across three consumers | Asset-backed visual recheck and general placement parity pending |
 | M2 placement grouper | Implemented extraction | Scene-free validation/order/transform/source/timing contract | Worker/build state, spatial cells and asset-backed p95/p99 remain pending |
 | M2 build batch planner | Implemented extraction | Scene-free limit/count/cursor/source/timing contract | Queue/resource state, spatial cells and asset-backed p95/p99 remain pending |
+| M2 prototype cache state | Implemented extraction | Synthetic identity/negative/lifecycle/source/timing plus shutdown contract | Asset-backed traversal/leak/p95/p99 pending |
 | WMO placement resolver | Implemented extraction | Scene-free path/identity/transform/source/timing contract | Asset-backed comparison pending |
 | WMO placement registry | Implemented extraction | Scene-free ownership/lifecycle/source/timing contract | Build/resource state and asset-backed cross-tile corpus pending |
 | WMO render build step planner | Implemented extraction | Scene-free order/cursor/source/timing contract | Asset-backed traversal p95/p99 pending |
@@ -596,6 +604,7 @@ Exact exported settings and cache versions remain documented in [`../../RENDER.m
 | `src/render/m2/m2_mesh_resource_extractor.gd` | First-Mesh selection and temporary PackedScene instance lifetime |
 | `src/render/m2/m2_runtime_mesh_finalizer.gd` | Runtime refresh version, rebuild classification/build and fallback |
 | `src/render/m2/m2_raw_model_repository.gd` | Stateless static/animated native M2 file boundary |
+| `src/render/m2/m2_prototype_cache_state.gd` | Detached prototype ownership and negative lookup outcomes |
 | `src/render/streaming/streaming_target_planner.gd` | Scene-free wanted/retained ADT target calculation |
 | `src/render/streaming/streaming_target_policy.gd` | Immutable renderer radius/prefetch policy |
 | `src/render/streaming/streaming_target_plan.gd` | Immutable planner result with read-only tile-key sets |
@@ -616,6 +625,7 @@ Exact exported settings and cache versions remain documented in [`../../RENDER.m
 | `src/tools/verify_m2_mesh_resource_extractor.gd` | M2 direct/PackedScene/subtree order/lifetime/boundary/timing regression |
 | `src/tools/verify_m2_runtime_mesh_finalizer.gd` | M2 current/stale/rebuild/fallback/boundary/timing regression |
 | `src/tools/verify_m2_raw_model_repository.gd` | M2 invalid/missing/native-boundary/dependency/timing regression |
+| `src/tools/verify_m2_prototype_cache_state.gd` | M2 prototype identity/negative/lifecycle/boundary/timing regression |
 | `src/tools/verify_streaming_target_planner.gd` | Planner behavior, dependency and bounded timing regression |
 | `src/tools/verify_render_budget_scheduler.gd` | Scheduler bounds, shared-lane priority, cancellation and timing regression |
 | `src/tools/verify_renderer_internal_access.gd` | Gameplay/EditorPlugin/registered renderer-tool boundary gate derived from private streamer fields |