Auto-detect output types (INT, FLOAT, STRING) on dynamic node refresh

API route now returns types alongside keys. JS sets output slot type
accordingly, giving correct colored dots and type-safe connections.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

json_loader.py

@@ -76,8 +76,20 @@ if PromptServer is not None:
             seq = 1
         data = read_json_data(json_path)
         target = get_batch_item(data, seq)
-        keys = list(target.keys()) if isinstance(target, dict) else []
+        keys = []
-        return web.json_response({"keys": keys})
+        types = []
+        if isinstance(target, dict):
+            for k, v in target.items():
+                keys.append(k)
+                if isinstance(v, bool):
+                    types.append("STRING")
+                elif isinstance(v, int):
+                    types.append("INT")
+                elif isinstance(v, float):
+                    types.append("FLOAT")
+                else:
+                    types.append("STRING")
+        return web.json_response({"keys": keys, "types": types})
 
 
 # ==========================================

web/json_dynamic.js

@@ -40,7 +40,7 @@ app.registerExtension({
                 const resp = await api.fetchApi(
                     `/json_manager/get_keys?path=${encodeURIComponent(pathWidget.value)}&sequence_number=${seqWidget?.value || 1}`
                 );
-                const { keys } = await resp.json();
+                const { keys, types } = await resp.json();
 
                 // Update output_keys widget for Python to read at execution time
                 const okWidget = this.widgets?.find(w => w.name === "output_keys");
@@ -54,14 +54,18 @@ app.registerExtension({
 
                 // Build new outputs, reusing existing slots to preserve links
                 const newOutputs = [];
-                for (const key of keys) {
+                for (let k = 0; k < keys.length; k++) {
+                    const key = keys[k];
+                    const type = types[k] || "*";
                     if (key in oldSlots) {
                         // Reuse existing slot object (keeps links intact)
-                        newOutputs.push(this.outputs[oldSlots[key]]);
+                        const slot = this.outputs[oldSlots[key]];
+                        slot.type = type;
+                        newOutputs.push(slot);
                         delete oldSlots[key];
                     } else {
                         // New key — create a fresh slot
-                        newOutputs.push({ name: key, type: "*", links: null });
+                        newOutputs.push({ name: key, type: type, links: null });
                     }
                 }