feat(tools): add base_url support to OpenAI TTS provider

[hanai]

What and Why

The OpenAI TTS provider previously had base_url hardcoded to https://api.openai.com/v1, making it impossible to use self-hosted or OpenAI-compatible TTS services.

This PR reads base_url from ~/.hermes/config.yaml under tts.openai.base_url, falling back to the official endpoint when not set. No behavior change for existing users.

Usage

tts:
  provider: openai
  openai:
    base_url: http://localhost:8000/v1  # e.g. LocalAI, or any OpenAI-compatible TTS endpoint
    voice: alloy

Changes

• tools/tts_tool.py: read base_url from oai_config in _generate_openai_tts()
• website/docs/user-guide/features/voice-mode.md: document the new base_url field under tts.openai

How to Test

1. Set tts.provider: openai and tts.openai.base_url: http://localhost:8000/v1 in ~/.hermes/config.yaml
2. Run hermes chat -q "Say hello" with TTS enabled — requests should go to the custom endpoint
3. Without base_url set, behavior is identical to before

Platform

Tested on macOS.

[Copilot]

Pull request overview

Adds configurability to the OpenAI TTS provider so Hermes can target self-hosted / OpenAI-compatible TTS endpoints via tts.openai.base_url in ~/.hermes/config.yaml, while preserving the existing default behavior.

Changes:

• Read tts.openai.base_url from config and pass it to the OpenAI client in the OpenAI TTS provider.
• Document TTS configuration (including OpenAI base_url) in cli-config.yaml.example.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
tools/tts_tool.py	Plumbs base_url from tts.openai config into the OpenAI client initialization.
cli-config.yaml.example	Adds a commented example block showing TTS configuration, including OpenAI base_url.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

You can also share your feedback on Copilot code review. Take the survey.