Add Parity to Websites

[mysticalseeker24]

Adds Parity to Websites.

Specialist-care booking, built for the OpenAI WebMCP Challenge, on one argument: building a site for agents is the same work as making it usable by the humans the interface locked out.

Why it may be of interest to this list

• One registry, two callers, literally. The Ctrl+K command palette is not a parallel command list — it calls document.modelContext.getTools() for discovery and executeTool() for execution, the same APIs the agent uses. A tool the palette has never heard of still renders, from its schema alone.
• Agentic browsing is currently an accessibility regression, and this is an attempt at the fix. When an agent fills a form, a screen-reader user is told nothing. Here every execution — agent- or human-initiated — emits an aria-live announcement naming the actor, worded by the tool's own announce().
• State-driven registration. 19 tools defined, never more than 8 live; get_booking_state.unavailable[] returns a reason_code and unlock_by for every tool that is not.
• Consent. Consequential tools require a grant hashed over the canonical arguments, expiring, consumed once — and the README says plainly that this is necessary, not sufficient while the host is also a computer-use agent, citing #288, which is reproduced and recorded rather than claimed solved.

Spec issues it has data on

Built against #255, #262, #277, #278, #282, #286 and #288, with issue numbers in the code. It also independently reproduced #300 in Chrome 152: because the live set is derived from page state, a tool routinely unregisters itself mid-execute, and the caller was then rejected with "The operation failed for an unknown transient reason" after the action had already succeeded — an agent told a booking failed when the appointment exists. Notes and the mitigation are in the repo.

No server, no MCP endpoint — a static SPA. Verified in Chrome 152 with --enable-blink-features=WebMCP; 385 unit tests and 36 assertions driven against real Chrome over CDP.

Source: https://github.com/mysticalseeker24/parity-webmcp

[Copilot]

🟢 Approval recommended

The change is a straightforward documentation-only addition consistent with the PR’s stated goal and does not introduce code or behavioral risk.

Pull request overview

Adds Parity to the “Websites” registry list in this repo’s README, expanding the catalog of real-world WebMCP-enabled sites.

Changes:

• Added a new “Parity” entry under Websites, including a short description of its tool registry/caller model, accessibility announcements, and consent/grant mechanism.
• Linked to the deployed site and the project source repository.

File summaries

File	Description
README.md	Adds Parity to the Websites list with a detailed feature-oriented description and source link.

Review details

• Files reviewed: 1/1 changed files
• Comments generated: 0
• Review effort level: Lite

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.