Windows Sites publication blocked at write_stdin despite granted network and Git-directory permissions #53292

Summary

Updating an existing Sites project is blocked at the official source-workflow helper's stdin step. Reproduced on 2026-10-12 (Asia/Seoul) in the Windows desktop app with PowerShell and Sites plugin 1.0.1. Exact desktop app version and subscription were not verified in this session.

Possibly related to #53134, #50874 and #52517. This report records a further reproduction with explicit request_permissions grants.

Steps to reproduce

1. Request edits and publication of an existing Sites website.
2. Read the existing project identity and obtain a fresh source repository write credential through the Sites connector.
3. Use request_permissions for network access and write access to the existing checkout's .git directory. The tool returns both permissions granted for the turn.
4. Start the official site-workflow.mjs helper using exec_command with tty=true from the existing checkout.
5. Wait for Ready for Site workflow JSON on stdin (input is hidden).
6. Send the credential object as newline-terminated JSON using write_stdin, as required by the Sites skill.

Actual result

The write_stdin tool rejects the call before the helper can process it:

write_stdin rejected: approval required by policy, but AskForApproval::Granular.sandbox_approval is false

The runtime describes a granular policy with sandbox_approval=false and request_permissions=true. Granting the requested network and Git-directory permissions does not resolve the rejection. A fresh credential and a newly started helper session still reproduce the failure. The app's visible permission selection was not independently inspected.

Expected result

The supported Sites workflow should be able to deliver input after the required scoped permissions are granted, or the app should surface an actionable approval prompt / explain the higher-priority policy blocking it.

Impact and scope

Local source edits and builds work, and 26 local application tests pass, but source synchronization and publication cannot proceed. Sites metadata operations work. No new version was published, and no production records were deleted. Tokens, site identifiers, local user paths, member data and raw conversation logs are intentionally omitted.

Please investigate the mismatch between granted scoped permissions and the write_stdin approval category, and provide a supported recovery path that does not require disabling security protections.