fix: resolve prompt variables through router nodes for PromptConstructor

Variables from upstream Prompt nodes weren't discovered when a Router sat
between the Prompt and PromptConstructor. Added resolveTextSourcesThroughRouters()
helper that recursively traverses router nodes to find actual text sources,
used in both the component and executor.

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

src/components/nodes/PromptConstructorNode.tsx

@@ -6,6 +6,7 @@ import { BaseNode } from "./BaseNode";
 import { usePromptAutocomplete } from "@/hooks/usePromptAutocomplete";
 import { useWorkflowStore } from "@/store/workflowStore";
 import { PromptConstructorNodeData, PromptNodeData, LLMGenerateNodeData, AvailableVariable } from "@/types";
+import { resolveTextSourcesThroughRouters } from "@/store/utils/connectedInputs";
 import { parseVarTags } from "@/utils/parseVarTags";
 
 type PromptConstructorNodeType = Node<PromptConstructorNodeData, "promptConstructor">;
@@ -31,10 +32,11 @@ export function PromptConstructorNode({ id, data, selected }: NodeProps<PromptCo
 
   // Get available variables from connected prompt nodes (named variables + inline <var> tags)
   const availableVariables = useMemo((): AvailableVariable[] => {
-    const connectedTextNodes = edges
+    const directTextNodes = edges
       .filter((e) => e.target === id && e.targetHandle === "text")
       .map((e) => nodes.find((n) => n.id === e.source))
       .filter((n): n is typeof nodes[0] => n !== undefined);
+    const connectedTextNodes = resolveTextSourcesThroughRouters(directTextNodes, nodes, edges);
 
     const vars: AvailableVariable[] = [];
     const usedNames = new Set<string>();

src/store/execution/simpleNodeExecutors.ts

@@ -18,6 +18,7 @@ import type {
   WorkflowNode,
 } from "@/types";
 import type { NodeExecutionContext } from "./types";
+import { resolveTextSourcesThroughRouters } from "@/store/utils/connectedInputs";
 import { parseTextToArray } from "@/utils/arrayParser";
 import { parseVarTags } from "@/utils/parseVarTags";
 
@@ -109,11 +110,12 @@ export async function executePromptConstructor(ctx: NodeExecutionContext): Promi
     const edges = getEdges();
     const nodes = getNodes();
 
-    // Find all connected text nodes
+    // Find all connected text nodes (resolving through routers)
-    const connectedTextNodes = edges
+    const directTextNodes = edges
       .filter((e) => e.target === node.id && e.targetHandle === "text")
       .map((e) => nodes.find((n) => n.id === e.source))
       .filter((n): n is WorkflowNode => n !== undefined);
+    const connectedTextNodes = resolveTextSourcesThroughRouters(directTextNodes, nodes, edges);
 
     // Build variable map: named variables from Prompt nodes take precedence
     const variableMap: Record<string, string> = {};

src/store/utils/connectedInputs.ts

@@ -119,6 +119,41 @@ function getSourceOutput(
   return { type: "image", value: null };
 }
 
+/**
+ * Resolves text source nodes through router (passthrough) nodes.
+ * Given a list of directly-connected source nodes, expands any router nodes
+ * by recursively following their upstream text connections to find the actual
+ * text-producing source nodes.
+ */
+export function resolveTextSourcesThroughRouters(
+  sourceNodes: WorkflowNode[],
+  allNodes: WorkflowNode[],
+  edges: { source: string; target: string; targetHandle?: string | null }[],
+  visited?: Set<string>
+): WorkflowNode[] {
+  const seen = visited ?? new Set<string>();
+  const resolved: WorkflowNode[] = [];
+
+  for (const node of sourceNodes) {
+    if (seen.has(node.id)) continue;
+    seen.add(node.id);
+
+    if (node.type === "router") {
+      const upstreamNodes = edges
+        .filter((e) => e.target === node.id && e.targetHandle === "text")
+        .map((e) => allNodes.find((n) => n.id === e.source))
+        .filter((n): n is WorkflowNode => n !== undefined);
+      resolved.push(
+        ...resolveTextSourcesThroughRouters(upstreamNodes, allNodes, edges, seen)
+      );
+    } else {
+      resolved.push(node);
+    }
+  }
+
+  return resolved;
+}
+
 /**
  * Get all connected inputs for a node.
  * Pure function version of workflowStore.getConnectedInputs.