blog-audio

Blog Audio: Gemini TTS Narration for Blog Posts

Generate professional audio narration of blog content using Google's Gemini TTS. Three modes: summary (200-300 word spoken overview), full article read-aloud, or two-speaker podcast dialogue. 30 voices, 80+ languages, HTML5 embed output.

Quick Reference

Prerequisites

• Python 3.11+ (venv managed automatically by run.py)
• GOOGLE_AI_API_KEY environment variable (same key used by blog-image)
• FFmpeg (for WAV-to-MP3 conversion; falls back to WAV if missing)

Always Use run.py Wrapper

# CORRECT:
python3 scripts/run.py generate_audio.py --text "..." --voice Charon --json
 
# WRONG:
python3 scripts/generate_audio.py --text "..."

API Key Check (Gate Pattern)

Before generating audio, check for the API key:

• If set: proceed with generation
• If not set: guide the user: "Audio generation requires a Google AI API key. Get one free at https://aistudio.google.com/apikey Then set it: export GOOGLE_AI_API_KEY=your-key This can be the same key used by /blog image, but it must be exported in the shell."
• When called internally (from blog-write): return silently if key is missing. Never block the writing workflow.

Setup

For /blog audio setup:

1. Check if GOOGLE_AI_API_KEY is set in environment
2. If blog-image uses project .mcp.json, confirm the referenced env var is exported
3. If not, guide user to https://aistudio.google.com/apikey
4. Verify with a dry run: python3 scripts/run.py generate_audio.py --text "Test" --dry-run --json

Voice Selection

For /blog audio voices:

Load references/voices.md and present the voice catalog to the user.

Ask the user which voice they prefer, or recommend based on content type:

• Article narration: Charon (Informative) or Sadaltager (Knowledgeable)
• Tutorial/how-to: Achird (Friendly) or Sulafat (Warm)
• News/analysis: Rasalgethi (Informative) or Schedar (Even)
• Lifestyle/wellness: Aoede (Breezy) or Vindemiatrix (Gentle)
• Dialogue host: Puck (Upbeat) or Laomedeia (Upbeat)
• Dialogue expert: Kore (Firm) or Charon (Informative)

Generation Workflow

For /blog audio generate <file>:

Step 1: Read the Blog Post

Read the file and extract:

• Title (from H1 or frontmatter)
• Full content (markdown body)
• Approximate word count

Step 2: Choose Mode

Ask the user (or auto-select if they specified --mode):

Step 3: Prepare Text

Claude prepares the text; the script does TTS only.

Summary mode: Write a 200-300 word spoken summary of the article. Rules:

• Write as natural speech, not written text
• Open with the article's key finding or answer
• Cover 3-5 main takeaways
• Close with actionable advice
• No markdown, no "In this article...", no meta-commentary
• Use conversational transitions ("Here's what matters...", "The key finding is...")

Full mode: Strip the markdown content to clean spoken text:

• Headings become natural transitions ("Next, let's look at...")
• Links become plain text (remove URLs, keep anchor text)
• Images and charts: omit or briefly describe ("As the data shows...")
• Code blocks: describe verbally ("The code uses a for-loop to...")
• Lists: convert to natural sentences
• Remove frontmatter, schema markup, HTML tags
• Add brief intro: "This is [title], published on [date]."

Dialogue mode: Write a 2-person conversation script about the article:

• Speaker1 = Host (curious, asks good questions)
• Speaker2 = Expert (knowledgeable, gives clear answers)
• Format each line as: Speaker1: What's the key takeaway here?
• Cover the article's main points conversationally
• 15-25 exchanges (produces ~3-8 minutes)
• Natural, not stilted ("That's a great point" over "Indeed, as the research indicates")

Step 4: Select Voice

If the user chose a voice, use it. Otherwise, recommend based on mode:

• Summary/Full: default to Charon (Informative)
• Dialogue: default to Puck (Host) + Kore (Expert)

Step 5: Generate Audio

Write the prepared text to a file under the working directory, then call:

Model selection:

• flash (default): maps to gemini-3.1-flash-tts-preview, good for summaries and standard narration.
• flash31: explicit alias for gemini-3.1-flash-tts-preview.
• legacy-flash25: retained only for older compatibility.
• pro or legacy-pro25: maps to gemini-2.5-pro-preview-tts, use only when needed.

Step 6: Deliver

Present the result to the user:

1. File path: where the audio was saved
2. Duration: human-readable (e.g., "3:42")
3. Embed code: ready-to-paste HTML5 audio tag
4. Cost: estimated API cost
5. Placement suggestion: where to insert the embed in the blog post

Embedding Guide

Standard HTML (Hugo, Jekyll, static sites)

MDX (Next.js, Gatsby)

WordPress

Placement

Insert the audio player after the introduction (below the first H2) or at the very top of the article with a label: "Listen to this article" or "Audio version".

Internal API (for blog-write)

When invoked internally from blog-write:

Input:

• text: Prepared text (already cleaned by Claude)
• voice: Voice name (default: Charon)
• voice2: Second voice for dialogue (optional)
• model: flash or pro
• output_path: Where to save the file

Output:

Graceful fallback: If GOOGLE_AI_API_KEY is not set, return immediately with no error. The writing workflow continues without audio. Never block blog-write because audio generation is unavailable.

Error Handling

Reference Documentation

Load on-demand: do NOT load all at startup:

• references/voices.md: Full 30-voice catalog, recommendations by content type, dialogue pairings