[BUG] Opus 4.7 thinking renders empty/unexpandable stub in VS Code extension

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?

In VS Code, Claude Opus 4.7 shows "Thinking for Xs" but the block has no content and cannot be expanded. On Opus 4.6 (now removed) the thinking summary displayed and expanded inline like normal. Confirmed same broken behavior in the official Claude app, so this isn't VS Code specific — but since 4.6 has been retired, there's no way to opt out or see reasoning at all anymore. Running Claude Code 2.1.112 on macOS.

What Should Happen?

Clicking the "Thinking for Xs" block should expand it to show Claude's reasoning summary, the same way it worked on Opus 4.6. Since 4.6 has been retired and 4.7 is the only Opus option, summarized thinking should be visible by default — or there should be a user-facing setting to enable it. Right now there's no way to see Claude's reasoning in either the VS Code extension or the official Claude app.

Error Messages/Logs

No error messages. Thinking block renders silently as an inert "Thinking for Xs" stub with no expand control and no content. No console errors in VS Code, no stderr output from the Claude Code CLI.

Steps to Reproduce

. Install Claude Code v2.1.112 (CLI + VS Code extension anthropic.claude-code-2.1.112-darwin-x64).

1. Open any project in VS Code and open the Claude Code panel.
2. Confirm the active model is claude-opus-4-7 (the only Opus option now that 4.6 has been retired).
3. Send a prompt complex enough to trigger extended thinking, e.g.:

"Analyze the architecture of this project and suggest three scaling improvements."

1. Observe that a "Thinking for Xs" indicator appears above the response.
2. Attempt to click/expand the thinking block.

Expected: block expands to show Claude's reasoning summary (as it did on Opus 4.6).
Actual: block is inert — no expand control, no content, clicking does nothing.

Repros 100% of the time on every prompt. No project-specific code is needed — a blank VS Code workspace with a single "hello" prompt reproduces the same empty thinking stub.

Environment:

• Claude Code CLI: 2.1.112
• VS Code extension: anthropic.claude-code-2.1.112-darwin-x64
• Model: claude-opus-4-7
• OS: macOS 15.4 (Darwin 24.4.0)
• Shell: zsh

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Claude Code 2.1.101 with Opus 4.6. Thinking summaries displayed and expanded inline as expected. The regression appeared after the upgrade to 2.1.112 with Opus 4.7 replacing 4.6 as the only available Opus model.

Claude Code Version

2.1.112 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

Likely root cause (per Anthropic's own docs):

Opus 4.7 changed the API default for thinking.display from "summarized" to "omitted" — thinking blocks still appear in the response stream, but the thinking field is empty unless the caller explicitly sets display: "summarized". See:

• https://platform.claude.com/docs/en/about-claude/models/whats-new-claude-4-7
• https://platform.claude.com/docs/en/build-with-claude/extended-thinking

It appears Claude Code (and the official Claude app) were not updated to pass display: "summarized" for Opus 4.7, so the thinking field arrives empty and the UI has nothing to render.

Tried without success:

• Upgrading from 2.1.101 → 2.1.112 (release notes indicated 2.1.111 added Opus 4.7 support)
• Fully quitting and relaunching VS Code after the CLI upgrade
• Anthropic's Fin support bot suggested "showThinkingSummaries": true in ~/.claude/settings.json — that key does not exist in any official docs, settings schema, or the anthropics/claude-code GitHub repo; setting it had no effect (Fin hallucinated it)

Suggested fix:
Either default thinking.display to "summarized" for interactive Claude Code sessions on Opus 4.7, or expose a settings.json key (e.g. thinking.display) so users can opt in. Right now there is no way to see Claude's reasoning on any Anthropic surface since Opus 4.6 was retired.