Python: Clarify binary content purview classification

dotnet/src/Microsoft.Agents.AI.Purview/README.md

@@ -384,6 +384,16 @@ content are serialized to text. Only `UsageContent` is skipped, because it carri
 than user data. Text annotations such as citations, `ErrorContent.Details` and `DataContent.Name`
 are submitted as additional text entries.
 
+### Binary content uses text activities
+
+Both the agent and chat middleware evaluate all prompt content as `UploadText` and all response content
+as `DownloadText`, including binary content. The middleware cannot reliably distinguish a file
+attachment from inline binary content. Sending bytes as Purview binary content does not change the
+activity to `UploadFile` or `DownloadFile`.
+
+Configure DLP policies for `UploadText` and `DownloadText` to cover this content. Policies that block
+only `UploadFile` or `DownloadFile` do not block binary content through this integration.
+
 ### Remote references are not dereferenced
 
 Purview classifies the content it is handed; a reference to content is not the content.

python/packages/purview/README.md

@@ -474,6 +474,17 @@ Evaluation covers the response as it stands when the middleware runs. Because mi
 the response afterwards, what is evaluated depends on where the middleware is attached — see
 [Middleware order matters](#middleware-order-matters).
 
+### Binary content uses text activities
+
+Both `PurviewPolicyMiddleware` and `PurviewChatPolicyMiddleware` evaluate all prompt content as
+`UploadText` (`Activity.UPLOAD_TEXT`) and all response content as `DownloadText`
+(`Activity.DOWNLOAD_TEXT`), including binary content. The middleware cannot reliably distinguish a file
+attachment from inline binary content. Sending bytes as Purview binary content does not change the
+activity to `UploadFile` or `DownloadFile`.
+
+Configure DLP policies for `UploadText` and `DownloadText` to cover this content. Policies that block
+only `UploadFile` or `DownloadFile` do not block binary content through this integration.
+
 ### Remote references are not dereferenced
 
 Purview classifies the content it is handed; a reference to content is not the content.

skills/agent-framework-builder-dotnet/references/integrations.md

@@ -49,6 +49,11 @@ diagnostics already caught and returned by generated code.
 For AG-UI, remember that thread and run IDs are correlation identifiers, not authentication boundaries. The
 application owns authorization, durable snapshots, scaling, and rendering policy.
 
+For Purview, all prompt content uses the `UploadText` activity and all response content uses `DownloadText`,
+including binary content. The middleware cannot reliably distinguish file attachments from inline binary
+content. Configure DLP policies for these text activities; `UploadFile`-only or `DownloadFile`-only rules do
+not block binary content through this integration.
+
 ## Selection checklist
 
 Confirm the provider/service, authentication model (prefer token credentials), required capabilities, package

skills/agent-framework-builder-python/references/integrations.md

@@ -44,6 +44,11 @@ client when its lifetime must extend beyond any one agent context. Do not assume
 For AG-UI, remember that thread and run IDs are correlation identifiers, not authentication boundaries. The
 application owns authorization, durable snapshots, scaling, and rendering policy.
 
+For Purview, all prompt content uses the `UploadText` activity (`Activity.UPLOAD_TEXT`) and all response
+content uses `DownloadText` (`Activity.DOWNLOAD_TEXT`), including binary content. The middleware cannot
+reliably distinguish file attachments from inline binary content. Configure DLP policies for these text
+activities; `UploadFile`-only or `DownloadFile`-only rules do not block binary content through this integration.
+
 ## Code execution
 
 Monty and Hyperlight redact host tool exception diagnostics by default. Enable