Over the last 30 days, http://Sosumi.ai has served tens of millions of requests to coding agents looking up Apple docs, from about 6,900 (nice) unique IPs/day.
But does it actually help? I built an eval to find out: 41 Swift tasks, mostly new APIs in the OS 27 SDKs, checked by the compiler and per-task rules.
Without docs, Opus, GPT-6.1 Sol, and Sonnet pass about a third of them. With Sosumi, they pass 98%, 97%, and 94%.
Compared to built-in web search, Claude models score 12 to 30 points higher with Sosumi, at about half the cost or less. GPT does slightly better with web search (99%), but at 3× the cost.
Running the eval also turned up a handful of fixes, now live (one framework page was 3 MB 😬). The eval is open source: https://github.com/NSHipster/sosumi.ai/tree/main/evals/swift-api