VS Code: @terminal:name alone is rejected by chat input

Bug

In the Claude Code VS Code extension, typing @terminal:main (or any @terminal:name reference) as the sole content of a message shows a "No files found" dropdown and prevents the message from being sent. The input box interprets the @terminal: prefix as a file reference rather than a terminal mention.

Behavior matrix

| Input | Sends? | Notes |
|-------|--------|-------|
| @terminal:main | No | "No files found" dropdown appears, blocks send |
| @terminal:main (trailing space) | Yes | Terminal output attached correctly |
| text @terminal:main text | Yes | Terminal output attached correctly |
| @browser (alone) | Yes | Works fine |
| @ file picker (alone) | Yes | Works fine |

The underlying feature works — terminal output is correctly attached when the message does send. The issue is that the input box treats @terminal:name as a file picker query when it's the only content without trailing whitespace.

Additional note: incorrect AI context

The Claude model inside VS Code is given documentation stating that @file and @folder are typed syntax commands (e.g. @auth to fuzzy-match files, @src/components/ for folders). In reality, @ opens a file picker dropdown — there is no typed @filename syntax. This causes the AI to give users incorrect guidance about how to reference files.

Steps to Reproduce

1. Open Claude Code panel in VS Code
2. Name a terminal (e.g., "main")
3. Run some commands in that terminal so it has output
4. In the Claude Code chat input, type exactly @terminal:main (no trailing space)
5. Observe "No files found" dropdown appears
6. Attempt to send — message will not submit

Workaround

Add a trailing space after @terminal:main , or pad with surrounding text.

Environment

• OS: Windows 11 Pro 10.0.26200
• Claude Code VS Code extension: v2.1.87 (anthropic.claude-code)
• Model: Opus 4.6