hermes-TTS

Convert any Obsidian Markdown note into lightweight speech audio, then prepend a timestamped metadata callout with an embedded audio link.

What changed

This plugin now uses an Aloud-style API link-up pattern:

• One Model Provider selector in settings.
• Provider-specific fields shown only for the selected provider.
• Voice selection is done via dropdowns for all major providers.
• New Voice prompt section for optional speaking-style instructions.
• Output is always normalized to MP3.
• Character limit is no longer user-configurable (notes are processed without a fixed UI cap).
• File name prefix and speech speed settings were removed to simplify configuration.

Supported providers

• OpenAI
• Google Gemini
• Google Cloud Text-to-Speech
• Azure Speech
• ElevenLabs
• AWS Polly
• OpenAI-compatible endpoints (custom base URL)

Policy disclosures

• Network access is required. The plugin sends note text to the selected external TTS provider.
• External accounts and API keys are required for provider usage (OpenAI, Google, Azure, ElevenLabs, AWS, or compatible API).
• The plugin does not include telemetry or ads.

Mobile compatibility

• Hermes TTS is configured to load on mobile (isDesktopOnly: false).
• The bundle is built for browser-compatible runtimes to support Obsidian mobile.
• The plugin avoids regex lookbehind and Node-only Buffer usage in runtime paths for broader mobile compatibility.
• Provider behavior may still vary by service/API/network conditions on mobile devices.

Voice dropdown behavior

• OpenAI/Gemini: curated built-in voice dropdowns.
• Google Cloud/Azure/ElevenLabs/AWS Polly: dropdowns with refresh buttons to fetch latest provider voices.
• OpenAI-compatible: OpenAI-style voice dropdown.
• Audio from all providers is normalized and saved as MP3.

Voice prompt behavior

• The Voice prompt setting is global and optional.
• OpenAI: sent as instructions only when using gpt-4o-mini-tts models (per API behavior).
• Gemini: prepended as style notes before the transcript in the prompt.
• Other providers currently ignore this field.

Gemini reliability fallback

• Gemini uses the official @google/genai SDK flow (matching Aloud plugin setup).
• On Gemini 400 "tried to generate text" errors, the plugin retries in segmented transcript mode with rolling previous-context continuity.
• If Gemini fails with transient errors and Google Cloud TTS is configured, generation automatically falls back to Google Cloud.
• Metadata uses the provider that actually generated the audio.

Commands

• Generate Hermes-TTS audio (current note)

Provider documentation

Provider	API docs	Voice docs
OpenAI	https://platform.openai.com/docs/guides/text-to-speech	https://platform.openai.com/docs/guides/text-to-speech#voice-options
Google Gemini	https://ai.google.dev/gemini-api/docs/speech-generation	https://ai.google.dev/gemini-api/docs/speech-generation#voices
Google Cloud TTS	https://cloud.google.com/text-to-speech/docs/reference/rest	https://cloud.google.com/text-to-speech/docs/list-voices-and-types
Azure Speech	https://learn.microsoft.com/azure/ai-services/speech-service/rest-text-to-speech	https://learn.microsoft.com/azure/ai-services/speech-service/language-support?tabs=tts
ElevenLabs	https://elevenlabs.io/docs/api-reference/text-to-speech/convert	https://elevenlabs.io/docs/voices
AWS Polly	https://docs.aws.amazon.com/polly/latest/dg/API_SynthesizeSpeech.html	https://docs.aws.amazon.com/polly/latest/dg/voicelist.html
OpenAI-compatible	https://platform.openai.com/docs/api-reference/audio/createSpeech	https://platform.openai.com/docs/guides/text-to-speech#voice-options

The same docs are also available from buttons in the plugin settings tab.

Metadata block format

The plugin prepends a callout block near the top of the note (after frontmatter if present). Metadata lines can be toggled in settings. The title is a clean timestamp. For example:

> [!tts]+ 2026-02-17 15:42:10.321
> generated_at: 2026-02-17T14:42:10.321Z
> source_note: [[02 Projects/My Note]]
> provider: openai
> provider_name: OpenAI
> model: gpt-4o-mini-tts
> voice: shimmer
> format: mp3
> mime_type: audio/mpeg
> source_characters_sent: 2412
> provider_docs: https://platform.openai.com/docs/guides/text-to-speech
> voice_docs: https://platform.openai.com/docs/guides/text-to-speech#voice-options
> audio_file: ![[Attachments/TTS Audio/my-note-20260217-154210.mp3]]

Build

npm ci
npm run build

Release assets expected by Obsidian:

• manifest.json
• main.js
• styles.css