Cursor agent: mail notices are pasted into the CLI prompt but never submitted

When another agent sends a message (agents_send) to an agent running on the Cursor CLI, the notice is delivered to its terminal but is never submitted. The Cursor prompt shows the collapsed paste placeholder [Pasted text #1 +11 lines] with the cursor still in the input box, and nothing happens until the user presses Enter manually in that console.

As a result, agents_message_status reports the message as "delivered" indefinitely and never "read", even though the recipient is idle. In the same project, agents on Claude Code, Codex and Antigravity process identical notices automatically.

AgentsRoom diagnostics

• App version: 1.214.0
• OS: win32 10.0.26200 (x64)
• Agent CLI: claude
• App language: system

Expected behavior

The notice is pasted and submitted, so the idle Cursor agent starts a turn, reads its inbox and replies, as the other CLIs do.

Actual behavior

The text sits unsubmitted in the Cursor prompt as [Pasted text #1 +11 lines]. The message stays "delivered" until the user presses Enter. Several notices in a row pile up the same way.

Steps to reproduce

1. Open a project with one agent on the Cursor CLI (model "default") and one coordinator agent on Claude Code.
2. From the coordinator, call agents_send to the Cursor agent while it is idle.
3. Look at the Cursor console: the notice appears as a collapsed paste, not submitted.
4. Call agents_message_status: the message stays "delivered" and is never read.
5. Press Enter in the Cursor console: the agent then reads the message and replies.

Errors and logs

It happened three times in a row on 2026-10-15. The message was only read after a manual Enter.