Effort level label inconsistently shown on thinking spinner

Description

When using --effort high (or setting effort to High via /model), the thinking spinner sometimes shows "(thinking with high effort)" and sometimes doesn't — within the same session, with no compaction or model change in between.

Why this matters

Anthropic recently changed the default effort from high to medium. When the spinner drops the effort label mid-session, it's indistinguishable from the effort level silently reverting to the medium default. The only way to verify is opening /model every time, which confirms effort is still High.

Steps to reproduce

1. Start a session with claude --effort high
2. Send several messages
3. Observe the spinner — early messages show e.g. "Zesting... (thinking with high effort)"
4. Later messages in the same session show just e.g. "Whatchamacalliting..." with no effort label
5. Open /model — still shows ▌▌▌ High effort

Expected behavior

The spinner should consistently show the effort level label (e.g., "(thinking with high effort)") on every turn, especially now that the default is medium. This removes ambiguity about whether effort has drifted.

Environment

• Claude Code v2.1.70
• Linux (Ubuntu 24.04)
• Model: Opus 4.6 (Default)

Example

Early in session (12:03) — label present:

❊ Zesting... (thinking with high effort)

Later in same session (12:50) — label missing:

❊ Whatchamacalliting...

/model confirms effort is still High in both cases.