Our Story

The name Proxy403 comes from the HTTP 403 Forbidden error, the response AI crawlers and assistive technologies receive when a site blocks them. We're here to change that.

We started as a small team of accessibility engineers and AI researchers who kept seeing the same problem: companies investing in beautiful websites that were invisible to screen readers, AI agents, and users who needed accommodations most.

Today, Proxy403 offers automated site scanning, AI-powered site building, and a growing suite of tools to help any company, from startups to enterprise, become truly open on the web.

What is Agent Accessibility?

Agent accessibility is the practice of designing websites so that AI agents, autonomous software that browses, reads, and acts on the web on behalf of humans, can reliably understand and interact with them.

Traditional web accessibility focuses on humans: screen readers, keyboard navigation, color contrast, and cognitive load. Agent accessibility extends that mission to a new class of "user": the AI assistant that books your flights, summarizes your research, compares your insurance options, and fills out your forms.

A site that is agent-accessible exposes its meaning in machine-readable ways, through semantic HTML, structured data, clear labeling, and discovery files like robots.txt, llms.txt, and sitemap.xml. A site that isn't agent-accessible effectively returns a 403 Forbidden to the agentic economy, even if it looks beautiful to human eyes.

At Proxy403, we believe agent accessibility and human accessibility are two sides of the same coin. Build for both, and you build a site that truly works for everyone.

Inclusive by Design

We believe the web belongs to everyone, regardless of ability, device, or how they navigate.

Open to All Agents

The AI-powered internet needs sites that can be read by machines as clearly as by humans.

Standards-First

We follow WCAG 2.2, AGAG, and emerging AI accessibility norms so your site is future-proof.