Experimental public demo
A small WebMCP surface you can inspect.
When your browser supports the draft page-native WebMCP API, this page registers two deterministic, read-only tools. Everything they return is public and also readable on this page.
Public facts schema 2026-10-14 · No sign-in · No private browser state · No writes.
Runtime status
WebMCP is not available or enabled in this browser.
The WebMCP API is experimental and is not available in every browser. Unsupported browsers still get the complete human-readable demo and schemas below.
Bounded tool surface
Two tools. Public data only.
Both tools reject unknown fields and invalid arguments. Results are JSON strings with a small, versioned shape.
Static public facts
hronaut_public_facts
Requires exactly one topic: product, pricing, security, or demo-scope. Returns the schema version, the selected topic, and three short facts.
Example: {"topic":"demo-scope"}
Current stable release
hronaut_current_release
Requires an empty object. Validates the public /api/release response and returns only the schema version, semantic version, tag, a bounded summary, and the canonical GitHub release URL.
Example: {}
Deliberate boundary
This is not remote access to your browser.
This public demo uses document.modelContext to offer page-authored facts to a compatible in-page agent. It does not connect to the Hronaut desktop app, inspect your tabs, or invoke a wallet.
Hronaut’s desktop MCP server is a separate loopback Streamable HTTP service with optional owner-token authentication and workspace authorization. The desktop browser_webmcp tool is another, separate bridge: it lets an authorized local Hronaut client inspect or call tools that a loaded page deliberately exposes.
Fallback and source of truth
The facts stay useful without WebMCP.
- Product. Hronaut is a visible desktop Chromium browser. Named workspaces can persist across agent sessions. Its MCP endpoint is local loopback, not a hosted browser.
- Pricing. The trial lasts 10 days from the first agent tool call, with no credit card, and nothing is charged when it ends. A named-user subscription is $4 monthly or $24 yearly, for up to three devices.
- Security. The desktop MCP server listens on loopback by default; owner-token authentication is on for new profiles. Human-visible controls pause agent access and review sensitive actions. Published binaries are not currently platform code-signed or Apple-notarized.
Before relying on these facts, compare the current terms, security boundary, desktop tool catalog, and stable release manifest. This page should be re-verified before it is submitted to any public WebMCP directory.
Compatibility check, September 22, 2026
Verified in the Codex in-app browser on Linux, reporting Chromium 153 with document.modelContext enabled. The browser listed both tools; valid calls returned the bounded schemas above; an extra argument was rejected; and no console warning or error was emitted. This records one enabled experimental environment, not support in stock Chromium 153 or other browsers.
Primary sources