What you’ll need
- Hermes Agent 0.21.6 or later installed.
- An access key from app.ngrok.ai.
Install the plugin
Install the plugin with the Hermes CLI:NGROK_AI_GATEWAY_KEY.
Plugins are installed per Hermes profile, so install it again in any other profile that needs it.
Choose a model
Runhermes model and select ngrok AI Gateway, or pass --provider ngrok when you start Hermes.
The model list comes from your gateway, so it shows the models your access key is allowed to call, by full catalog ID such as openai/gpt-5.5.
Model IDs follow the gateway’s model naming: a model ID such as gpt-5.5, or provider:model to pin a provider, such as openai:gpt-5.5.
Test the connection
Send a single prompt from the command line:Use a cheaper model for background tasks
Background tasks like context compression and title generation use your main model. To send them to a cheaper model through the gateway, set the provider and model for each task in~/.hermes/config.yaml:
What the plugin sends
The plugin sends chat and model list requests tohttps://gateway.ngrok.ai/v1 with your access key.
Each request carries a User-Agent: hermes-agent/<version> (ngrok-plugin) header.
The plugin makes no other network requests, doesn’t read files, and doesn’t run background processes.
Next steps
- Restrict providers and models: Scope what an access key can call
- Configure fallback models: Try another model when the first one fails
- Observability: See which model served each request