Sierra Acquires Browser-Agent Startup Anon
Sierra announced that it has acquired Anon, whose browser-use infrastructure enables enterprise AI agents to navigate websites, sign in and complete forms even when no API is available. Anon's stack reportedly covers authentication, credential handling, browser infrastructure, an agent harness and an embeddable SDK, with capabilities claimed for sensitive data and multi-factor authentication workflows. Sierra says Anon's technology will support longer-running Horizon agent tasks that cross systems without APIs, but the reported capabilities and reliability lack independent verification.
The acquisition brings browser-based authentication and action infrastructure to Sierra's enterprise AI agents, potentially expanding their ability to complete workflows across systems that do not expose APIs.
We built Anon to help enterprise AI agents securely use websites the way people do. That means navigating pages and taking actions like signing in or filling out forms, even when there’s no API. We’re excited to share that Anon is joining Sierra, bringing our team’s expertise and access to our technology to agents that already handle billions of customer interactions each year.
Building Anon
Before Anon, I co-founded Spring Labs and spent years working on identity and data security for financial services companies. As AI agents started to emerge in early 2023, I saw a problem that felt familiar. If agents were going to act for people, they’d need a secure way to sign in and take action as them.
Our first implementation of this was an AI personal assistant. It got a lot of early use, but it showed us the bigger opportunity was building infrastructure for the wave of AI agents to come. We thought of it as “Plaid for AI agents.”
Building it took us deep into browser use. Most of what people do online happens behind a login, in interfaces built for people versus for software, and with no API. We built the stack to help agents work in those environments. That included authentication and credential handling, browser infrastructure, an agent harness, and an SDK developers could embed in their products.