Markdown prompt editor tab with “Send to active thread”

[seifkhaled123]

Problem / use case

I'd like a dedicated place inside T3 Code to write and revise longer prompts in Markdown while keeping the conversation visible. This is useful for prompts with requirements, headings, checklists, and code examples.

The workflow I want is: open a prompt editor tab alongside the existing Files, Diffs, and Browser tabs, write my prompt, then press one button to send it to the active thread and let the agent continue. This would avoid writing in an external editor and copying the result into the composer.

Proposed behavior

• Add a Prompt tab to the workspace panel alongside the existing tabs.
• Let me edit raw Markdown, preserving headings, lists, fenced code blocks, and line breaks. Enter should insert a new line.
• Provide a Send to active thread button that submits the draft as a normal user message and starts the agent, rather than only copying text into the composer.
• Show the destination thread's name beside the send action so the target is clear when switching between threads.
• Preserve the draft when switching panel tabs, and retain it if sending fails.
• Reuse the normal composer's rules for sending or queueing when the destination thread is already running. Avoid silently replacing any separate draft already in the composer.

Markdown syntax highlighting and an optional rendered preview would be useful, but the editor and direct-send action are the core request.

Smallest useful scope

Desktop and web first: one Markdown draft editor and a send action targeting the active thread. A prompt library, templates, AI prompt rewriting, and mobile support could stay outside the initial scope.

Related discussions

• Dock the composer beside the thread for long prompts #31571 proposes docking the composer beside the thread for long prompts. This request overlaps with that use case, with a preference for a dedicated Markdown editor tab in the existing workspace panel.
• [Feature request] "Bucket/Notepad" for upcoming prompts linked to a thread #31884 proposes a notepad for upcoming prompts linked to a thread. This request adds an explicit action to submit the drafted prompt to the active thread.

Would this fit the direction of T3 Code, either as its own panel tab or as part of the docked-composer proposal?