diff --git a/app/api/canvas/detail-plan/route.ts b/app/api/canvas/detail-plan/route.ts
index 4eb7035c6..f013ba7d9 100644
--- a/app/api/canvas/detail-plan/route.ts
+++ b/app/api/canvas/detail-plan/route.ts
@@ -5,11 +5,26 @@ import {
   getAgentAiModelWithProvider,
   getEnabledAiModelsWithProvider,
 } from "@/lib/db/queries";
+import { isAiModelMultimodal } from "@/lib/db/ai-model-flags";
 import { getLanguageModelById } from "@/lib/ai/dynamic-provider";
 
 export const runtime = "nodejs";
 export const maxDuration = 60;
 
+function supportsVisionPlanning(model: {
+  supportsVision?: boolean | null;
+  capabilities?: unknown;
+  defaultParams?: unknown;
+}) {
+  return (
+    Boolean(model.supportsVision) ||
+    isAiModelMultimodal({
+      capabilities: model.capabilities,
+      defaultParams: model.defaultParams,
+    })
+  );
+}
+
 type DetailPlanRequest = {
   prompt?: string;
   count?: number;
@@ -738,8 +753,8 @@ export async function POST(request: Request) {
     let plannerConfig = preferredAgentConfig;
 
     if (referenceImages.length > 0) {
-      if (!plannerConfig?.model.supportsVision) {
-        plannerConfig = reasoningCompatible.find((item) => item.model.supportsVision);
+      if (!plannerConfig || !supportsVisionPlanning(plannerConfig.model)) {
+        plannerConfig = reasoningCompatible.find((item) => supportsVisionPlanning(item.model));
       }
     }
     if (!plannerConfig) {
@@ -750,6 +765,19 @@ export async function POST(request: Request) {
       return NextResponse.json({ success: true, data: fallback });
     }
 
+    console.log("[Canvas Detail Plan] Planner model selected:", {
+      id: plannerConfig.model.id,
+      displayName: plannerConfig.model.displayName,
+      modelId: plannerConfig.model.modelId,
+      providerType: plannerConfig.provider.type,
+      supportsVision: plannerConfig.model.supportsVision,
+      multimodalFlag: isAiModelMultimodal({
+        capabilities: plannerConfig.model.capabilities,
+        defaultParams: plannerConfig.model.defaultParams,
+      }),
+      hasReferenceImages: referenceImages.length > 0,
+    });
+
     const model = await getLanguageModelById(plannerConfig.model.id);
     if (!model) {
       return NextResponse.json({ success: true, data: fallback });
@@ -776,7 +804,7 @@ export async function POST(request: Request) {
       .join("\n");
 
     const imageInputs =
-      plannerConfig.model.supportsVision && referenceImages.length > 0
+      supportsVisionPlanning(plannerConfig.model) && referenceImages.length > 0
         ? referenceImages.map((url) => ({ type: "image" as const, image: url }))
         : [];