[BUG] Read/file-viewer tool output renders as non-copyable webview link, not plain text

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

What's wrong: When Claude Code uses its file-viewer ("Read") tool to display file contents in the VS Code/Antigravity extension panel, the output renders as a clickable vscode-webview://... reference (e.g. "Read file.md (lines X-Y)") rather than as selectable plain text. Copying this into another application only captures the link label, not the actual file content — even though Claude's own message describes the content as being shown "verbatim above."

Reproduction: Ask Claude Code to view/read a section of a file and then try to copy that content out for use elsewhere (e.g. pasting into another chat or document). The Read tool's rendered output cannot be copy/pasted as plain text — only the bash tool's output (via cat/sed/head) behaves correctly.

Workaround in use: explicitly instructing the agent to use bash (cat, sed -n, head/tail) instead of its Read/view tool whenever literal copyable output is needed.

Possibly related: issue #78256 (similar webview-rendering regression reported previously).

What Should Happen?

Reading a file's contents in the Claude Code panel should render as plain, selectable text (or otherwise be copyable in full), the same way bash tool output (cat, sed -n, head/tail) already renders. A user should be able to select and copy the actual file content shown by the Read tool — not just a clickable vscode-webview://... link label — without needing to route the same request through bash as a workaround.

Error Messages/Logs

Steps to Reproduce

Open Claude Code inside the Antigravity/VS Code extension panel, connected to any repository.
Ask Claude Code to view a file or section of a file — e.g. "Read README.md" or "Show me lines 1–50 of package.json" — such that it uses its Read/file-viewer tool (not bash).
Observe the tool's output rendered in the panel: a collapsed reference like "Read README.md (lines 1–50)" rather than the file's actual text inline.
Attempt to select and copy that rendered output — either by clicking/dragging to select it, or using standard copy commands.
Paste the copied content elsewhere (e.g. a text editor, another chat window, a terminal).
Observed: the paste contains only the link label / tool-call reference (e.g. "Read README.md (lines 1–50)"), not the actual file contents — even though Claude's accompanying message describes the content as shown "verbatim above."
For comparison: ask Claude Code to instead run cat README.md or sed -n '1,50p' README.md via its bash tool. That output renders as plain text in the panel and copies correctly in full — confirming the bug is specific to the Read/file-viewer tool's rendering, not a general panel/copy limitation.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.215 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

Google's Antigravity claude code extension