Simon Willison’s Weblog

Headless everything for personal AI. Matt Webb thinks headless services are about to become much more common:

Why? Because using personal AIs is a better experience for users than using services directly (honestly); and headless services are quicker and more dependable for the personal AIs than having them click round a GUI with a bot-controlled mouse.

Evidently Marc Benioff thinks so too:

Welcome Salesforce Headless 360: No Browser Required! Our API is the UI. Entire Salesforce & Agentforce & Slack platforms are now exposed as APIs, MCP, & CLI. All AI agents can access data, workflows, and tasks directly in Slack, Voice, or anywhere else with Salesforce Headless.

If this model does take off it's going to play havoc with existing per-head SaaS pricing schemes.

I'm reminded of the early 2010s era when every online service was launching APIs. Brandur Leach reminisces about that time in The Second Wave of the API-first Economy, and predicts that APIs are ready to make a comeback:

Suddenly, an API is no longer liability, but a major saleable vector to give users what they want: a way into the services they use and pay for so that an agent can carry out work on their behalf. Especially given a field of relatively undifferentiated products, in the near future the availability of an API might just be the crucial deciding factor that leads to one choice winning the field.