From 5e82adb7eb35c3ab06c5ae23ba9e34c406f6f3f4 Mon Sep 17 00:00:00 2001
From: 134 <a134@134deMacBook-Pro.local>
Date: Mon, 22 Jun 2026 22:19:54 +0800
Subject: [PATCH] fix: preserve canvas agent media metadata

---
 lib/canvas/agent-mutations.ts                |  1 +
 tests/routes/canvas-agent-operations.test.ts | 22 +++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/lib/canvas/agent-mutations.ts b/lib/canvas/agent-mutations.ts
index 1a7a4fdb8..8b4764cdf 100644
--- a/lib/canvas/agent-mutations.ts
+++ b/lib/canvas/agent-mutations.ts
@@ -116,6 +116,7 @@ function buildMediaNode(params: {
   const now = new Date().toISOString();
   const type = mediaNodeType(params.item);
   const metadata = {
+    ...(params.plan.metadata || {}),
     ...(params.item.metadata || {}),
     generatedByAgent: true,
     canvasAgentOperationId: params.plan.operationId,
diff --git a/tests/routes/canvas-agent-operations.test.ts b/tests/routes/canvas-agent-operations.test.ts
index 5c6944252..0c82561ff 100644
--- a/tests/routes/canvas-agent-operations.test.ts
+++ b/tests/routes/canvas-agent-operations.test.ts
@@ -361,7 +361,21 @@ test.describe("canvas agent operation mutation contract", () => {
         sourceNodeIds: ["image-source"],
         anchorNodeId: "image-source",
         placement: "right",
-        mediaItems: [buildMutationMediaItem("media-revision", ["image-source"])],
+        mediaItems: [
+          {
+            ...buildMutationMediaItem("media-revision", ["image-source"]),
+            prompt: "turn the background white",
+            metadata: {
+              model: "test-image-model",
+              provider: "test-provider",
+            },
+          },
+        ],
+        metadata: {
+          messageId: "assistant-message-1",
+          chatId: "chat-1",
+          model: "plan-level-model",
+        },
       },
     });
 
@@ -376,11 +390,17 @@ test.describe("canvas agent operation mutation contract", () => {
       type: "image",
       data: {
         src: "https://cdn.example.com/media-revision.png",
+        prompt: "turn the background white",
         metadata: {
           generatedByAgent: true,
           canvasAgentOperationId: "op-append-revision",
           canvasAgentMediaItemId: "media-revision",
           revisionOf: "image-source",
+          sourceNodeIds: ["image-source"],
+          messageId: "assistant-message-1",
+          chatId: "chat-1",
+          model: "test-image-model",
+          provider: "test-provider",
         },
       },
     });