fix(ai-sdk): log AI SDK v7 inline file data as attachments

Author: pmartinsdev

.changeset/ai-sdk-v7-inline-file-attachments.md

@@ -0,0 +1,5 @@
+---
+"braintrust": patch
+---
+
+fix(ai-sdk): log AI SDK v7 inline file data as attachments instead of copying the bytes into the span

js/src/instrumentation/plugins/ai-sdk-plugin.test.ts

@@ -32,6 +32,7 @@ import {
   BRAINTRUST_AI_SDK_V7_OPERATION_KEY as AI_SDK_V7_OPERATION_KEY,
 } from "../../vendor-sdk-types/ai-sdk-v7-telemetry";
 import { serializeAISDKToolsForLogging } from "../../wrappers/ai-sdk/tool-serialization";
+import { Attachment } from "../../logger";
 import {
   AISDKPlugin,
   DEFAULT_DENY_OUTPUT_PATHS,
@@ -221,6 +222,28 @@ describe("AISDKPlugin", () => {
       expect(processed.model).not.toHaveProperty("doStream");
       expect(processed.model.config).not.toHaveProperty("url");
     });
+
+    it("logs AI SDK v7 inline file data as attachments", () => {
+      const processed = processAISDKCallInput({
+        prompt: [
+          {
+            role: "user",
+            content: [
+              {
+                type: "file",
+                mediaType: "image/png",
+                data: {
+                  type: "data",
+                  data: new Uint8Array([137, 80, 78, 71, 13, 10, 26, 10]),
+                },
+              },
+            ],
+          },
+        ],
+      }).input as Record<string, any>;
+
+      expect(processed.prompt[0].content[0].data).toBeInstanceOf(Attachment);
+    });
   });
 
   describe("enable/disable", () => {

js/src/instrumentation/plugins/ai-sdk-plugin.ts

@@ -1939,7 +1939,7 @@ const processContentPart = (part: any): any => {
       (part.mimeType || part.mediaType)
     ) {
       const fileAttachment = convertDataToAttachment(
-        part.data,
+        unwrapInlineFileData(part.data),
         part.mimeType || part.mediaType,
         part.name || part.filename,
       );
@@ -1972,6 +1972,10 @@ const processContentPart = (part: any): any => {
   return part;
 };
 
+// AI SDK v7 tags inline file bytes as { type: "data", data }.
+const unwrapInlineFileData = (data: unknown): unknown =>
+  isObject(data) && data.type === "data" && "data" in data ? data.data : data;
+
 const convertImageToAttachment = (
   image: any,
   explicitMimeType?: string,