Cowork dictation stops ~2s after start on macOS Tahoe 26.4.1 — began immediately after auto-update to 1.15962.0 (039543); chat dictation unaffected

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?

Voice dictation in the Cowork/agent input cuts off roughly 2 seconds after I start speaking, even while I'm still talking. Cowork's own input level meter visibly registers my voice the whole time, so audio is reaching the recorder — but the recording session tears down at ~2s and stops capturing.

Reproducible via both the in-app microphone button and the keyboard shortcut, and in both hold and tap styles. The behavior is identical every time.

Dictation in the regular Claude chat box works perfectly on the same machine, same session, same mic — so this is specific to the Cowork audio/recording path, not the device.

This started immediately after Claude Desktop auto-updated to 1.15962.0 (039543) overnight. The prior build worked. I changed nothing else.

What Should Happen?

Holding (or tapping to start) dictation in the Cowork input should record continuously until I stop/release, transcribe my full speech, and insert the text — the same as the chat box dictation does on this machine.

Error Messages/Logs

No audio/mic/voice/transcription entries appear in ANY ~/Library/Logs/Claude/*.log file during the failure window. Verified with:

grep -riE 'audio|mic|voice|record|transcri|stream' ~/Library/Logs/Claude/*.log | grep -iE 'error|fail|denied|closed|stop|abort|empty|zero|null'

The only matches were unrelated: "stream-json" process spawns in coworkd.log, and rate_limit / "Tool permission stream closed before response received" entries in main.log. Nothing audio-related is logged when dictation drops — i.e. the failure produces no error in Claude's own logs.

[If you can add it: during the ~2s, does any text appear then stop, or does no text ever land? Note whichever you see — it distinguishes "session killed mid-stream" from "transcription never connected."]

Steps to Reproduce

1. Open Claude Desktop on macOS Tahoe 26.4.1, build 1.15962.0 (039543).
2. Go to Cowork and click into the dictation input.
3. Start dictation (mic button OR keyboard shortcut; hold or tap — all the same).
4. Speak continuously for more than 2 seconds.
5. Observe: the input meter registers voice, but recording stops ~2s in and capture ends, despite continued speech.
6. For contrast: repeat in the regular chat box — dictation works normally.

Ruled out beforehand: mic permission granted to Claude Desktop (toggled off/on, app restarted); built-in mic set as system default with input level moving while speaking; sudo killall coreaudiod; full Mac restart.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Unknown exact string — auto-replaced overnight by 1.15962.0. Worked on the immediately prior build; not recoverable from local logs.

Claude Code Version

1.15962.0 (039543) · SDK/CLI 2.1.187 · Node 24.16.0

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• Chat-box dictation works on the same machine/session, isolating this to the Cowork audio path.
• Cowork's input meter shows live audio during the failure, so audio reaches the recorder — the session is being terminated downstream (~2s in), not starved of input.
• Timing implicates the build: dictation worked the day before, broke immediately after the overnight auto-update to 1.15962.0 (built 2026-06-25T01:24:19Z). No other changes. Restart and killall coreaudiod did not help.
• Possibly related to #55865 (Code-tab dictation discards transcript on stop, macOS Tahoe 26.4.1) — same OS and in-app dictation surface, but a different tab (Cowork vs Code) and a different failure mode (recording terminates ~2s mid-speech rather than discarding cleanly on stop). Suggests a per-tab in-app dictation regression on Tahoe.
• Anthropic Desktop auto-updates have a history of introducing Cowork regressions that needed follow-up patches, so a build-introduced regression here is plausible.
• No user-side mitigation found (permissions, built-in mic, coreaudiod restart, full reboot, key-hold, focus-in-field all tried). Workaround in use: chat dictation / system-wide dictation tool typed into the focused Cowork field.

Build: Claude Desktop 1.15962.0 (039543) · SDK/CLI 2.1.187 · Node 24.16.0 · macOS Tahoe 26.4.1 (Apple Silicon, MacBook Air)