diff --git a/crates/rrt-runtime/src/smp.rs b/crates/rrt-runtime/src/smp.rs
index c75298b..99b1071 100644
--- a/crates/rrt-runtime/src/smp.rs
+++ b/crates/rrt-runtime/src/smp.rs
@@ -10856,6 +10856,11 @@ fn parse_real_grouped_effect_row_summary(
         row_shape = "scalar_assignment".to_string();
         semantic_family = "scalar_assignment".to_string();
     }
+    if descriptor_metadata.is_some_and(|metadata| metadata.parameter_family == "world_building_spawn")
+    {
+        row_shape = "building_spawn_batch".to_string();
+        semantic_family = "building_spawn_batch".to_string();
+    }
 
     let mut notes = Vec::new();
     if locomotive_name.is_some() {
@@ -11708,6 +11713,9 @@ fn build_real_grouped_effect_semantic_preview(
             };
             format!("Set {label} to {state}")
         }
+        "building_spawn_batch" => format!(
+            "Batch place {label} with scalar {raw_scalar_value}, count {value_byte_0x11}, and span words [{value_word_0x14}, {value_word_0x16}]"
+        ),
         "timed_duration" => format!(
             "Set {label} to {raw_scalar_value} for {value_word_0x14} years {value_word_0x16} months"
         ),
diff --git a/docs/rehost-queue.md b/docs/rehost-queue.md
index 88c8505..c5a8568 100644
--- a/docs/rehost-queue.md
+++ b/docs/rehost-queue.md
@@ -301,10 +301,12 @@ Working rule:
     EventEffects table proves the actual grouped descriptors are add-building slots, not
     special-condition verbs
   - the compact opcode-`8` frontier therefore shifts:
-    the next static-analysis pass should determine whether opcode `8` on that shell-owned
-    add-building strip means a distinct add-building shell flow, and then continue the candidate
-    bridge past the currently grounded `503..569` front half of the widened strip, not more
-    missing-label recovery
+    direct disassembly of `0x00430270` now shows that the add-building consumer does not branch on
+    grouped opcode at all for descriptor strip `503..613`; it consumes the descriptor-derived
+    candidate id, placement count byte `0x11`, and the packed span words at `0x14/0x16`.
+    The next static-analysis pass should therefore target the remaining span-field meaning and
+    shell-owned placement-flow ownership on that strip, then continue the candidate bridge past the
+    currently grounded `503..569` front half of the widened strip, not more missing-label recovery
   - the concrete owner strip above that bundle is grounded now too:
     `0x00433060` is the direct non-direct serializer loop that writes `0x4e99/0x4e9a/0x4e9b`,
     calls `0x00430d70` per live collection row, and sits beside the sibling `0x00433130` size/load