Add spellcheck / autocorrect support to the VS Code extension prompt input box

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Description:

The Claude Code VS Code extension's prompt input box doesn't support spellcheck or autocorrect. Since the input is a custom UI widget, it doesn't inherit spellcheck from VS Code editor extensions (e.g. Code Spell Checker) or from the OS-level autocorrect.

For users who spend significant time typing natural language prompts — often including domain-specific terminology — typos and misspellings are common and go unnoticed until after submission.

Proposed Solution

Requested behaviour:

Enable basic spellcheck (red underline on misspelled words) in the prompt input box
Ideally, integrate with VS Code's spellcheck extensions so users can leverage their existing custom dictionaries (e.g. cspell.json project-level word lists)
Bonus: right-click suggestion menu for corrections, consistent with standard text input behaviour
Why it matters:

Typos in prompts can cause Claude to misinterpret intent or echo back misspelled terms into generated code/docs
Users working in specialised domains (insurance, finance, medical) have large vocabularies that benefit from custom dictionaries

The prompt box is where users spend most of their interaction time — it should have the same text-editing affordances as other input surfaces

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_