It is useful when you give the HTTP endpoint to an AI agent to fetch some data or to wait for instructions, then the execution of the ralph loop comes under your control as the AI agent think they are doing some HTTP request. Good when you want to pause the AI agent to investigate and provide more prompts etc.
It also has an endpoint for adding messages, this way you can cross 2 gates(these HTTP endpoints are called gates) and let one agent do your work, the other one look at the work and provide instructions to the agent.
You will understand the concept right away, create gate copy paste the prompt into the agent(works very well on Codex for me) and wait a few moment until the agent does a CURL and start waiting, then type something from the chat-like interface.
The cloud based gates require a subscription(as I need to maintain a server) but on the macOS app you can have local gates on localhost for free. If you are not interested in the hosted gates just close the paywall and use the local gates on the macOS app.
I find it useful, use it all the time so I hope you find it useful too.
Forgot the link: https://apps.apple.com/us/app/promptgate/id6772730472
It works on iOS and macOS.