Scream

claude-must-scream

Give Claude a voice. A small CLI that pipes Claude's responses (or arbitrary text) through Gemini Flash TTS and plays the audio locally — so you can listen instead of read when your eyes are tired, or hear a long agent run wrap up while you're across the room.

The name is a nod to Harlan Ellison's I Have No Mouth, and I Must Scream. The AI in that story had no mouth and couldn't be silenced. The AI here gets a mouth and a 30-voice picker.

When to invoke

Trigger on:

• "Read that aloud" / "speak that"
• "TTS the last response"
• "/scream"
• "Play it back"
• "I want to hear it" / "let me listen"
• "Switch voice to X" / "change to a different voice"
• Any time the operator asks for audio output of conversation content.

Do NOT invoke for:

• Generating audio files for downstream use (this skill plays-and-discards).

Use Gemini TTS directly for file output.

• Voice input / dictation (this skill is output-only).
• Long-form audiobook narration (cap is 1,200 chars; designed for short

agent responses, not chapters).

Prereqs

• macOS (uses afplay for playback and say as offline fallback). Linux

support possible — patches welcome.

• Python 3.9+ (stdlib only — no requests, no playwright, no installs).
• One of:
• Gemini API key (primary, best quality), supplied either via the

GEMINI_TTS_API_KEY env var or a key file at ~/.config/claude-tts/gemini-tts.key (0600). The env var wins when both are present; the key file is the fallback so sessions already running when the var was first exported still reach Gemini — a process's environment is frozen at launch. See docs/setup.md for how to mint one.

• macOS say (no setup; lower quality but works offline + free).

Make the scream CLI callable:

ln -sf /scripts/scream.py ~/.local/bin/scream
chmod +x /scripts/scream.py

The verbs

# On-demand
scream speak --text "hello world"        # speak arbitrary text
scream last                              # speak the last assistant message in this session
echo "piped text" | scream speak         # stdin → TTS

# Voice management
scream voice list                        # show all 30 voices + character descriptions
scream voice pick                        # interactive numbered picker (writes config)
scream voice set Aoede                   # set default voice non-interactively
scream voice preview Fenrir              # synthesize a short test phrase in a voice

# Auto-mode (Stop hook reads every response)
scream auto on                           # toggle on (hook must be installed; see docs/hooks.md)
scream auto off                          # toggle off
scream auto status                       # show current state + config

# Self-check + control
scream test                              # env + API self-check
scream test --speak                      # also plays a test phrase
scream stop                              # interrupt current playback (kills afplay / say)

All speak and last invocations accept:

• --voice — override the configured default for one call
• --provider gemini|say — override the configured provider
• --max-chars N — override the length cap (default 1,200)
• --dry-run — print what would be spoken without playing

How Claude should use it

1. On /scream with no args, invoke scream last. The script auto-detects

the current session's jsonl and reads the last assistant message.

1. On /scream , invoke scream speak --text "". Strips

markdown automatically — don't pre-process.

1. On /scream voice, invoke scream voice pick for interactive selection,

or scream voice list if non-interactive output is wanted.

1. On /scream auto on|off, invoke scream auto on|off. If turning on and

the Stop hook isn't installed yet, point the user at docs/hooks.md for the one-time settings.json snippet.

1. On any failure, run scream test to diagnose which layer (env var,

API reach, voice name, model availability) broke.

Markdown stripping

Code fences, links, table rows, bold/italic markers, headers, and bare URLs are all stripped before synthesis. Code fences become "(code block omitted)" so the cap-length budget doesn't get blown on a 500-line example. The synthesized text should sound like prose, not punctuation soup.

Length cap

Default 1,200 characters (~10 seconds of speech, ~$0.001 per call at Gemini Flash TTS rates). The cap tries to land on a sentence boundary; if it can't, it appends "…". Override per-call with --max-chars. Override the default in ~/.config/claude-tts/config.json.

Configuration

Two files:

• ~/.config/claude-tts/config.json — user prefs (voice, provider,

max_chars, auto-mode flag, model). Written by scream voice set / scream auto on. Mode 0600. Not committed to the public repo.

• GEMINI_TTS_API_KEY env var — your API key. The script reads it but

never writes it anywhere. See docs/setup.md for the recommended pattern of storing the key in ~/.config/claude-tts/gemini-tts.key (0600) and exporting from your shell rc.

Limits / non-goals

• macOS-only for now. afplay + say are macOS binaries. Linux port

would swap to aplay / paplay and espeak-ng / mimic3. Patches welcome.

• No streaming. Synthesizes one chunk, plays it. Long responses feel

laggy by design — the cap exists for a reason.

• No transcription / STT. Output-only.
• One playback at a time. A second invocation while one is in flight

just queues a second afplay — they'll overlap. Use scream stop first if that's not what you want.

Setup walkthrough

See docs/setup.md for the full one-time setup, including how to mint a dedicated GCP API key restricted to the TTS API.

Companion skills

• update-config — if you want the Stop hook installed automatically.

See docs/hooks.md for the snippet it should add.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: Bobby-Gray
• Source: Bobby-Gray/claude-must-scream
• License: MIT

Install and usage instructions live in the source repository linked above.