One intent. Many websites.
Moving home is not one task. It creates repeated updates across council, energy, water, postal, insurance, broadband, and employer websites. People re-enter the same information, compare consequences, remember which services changed, and trust that nothing outside their intent was touched.
RELAY is a one-screen coordination workspace for this life event. A person enters their current address, destination, move date, forwarding period, and approval threshold once. RELAY converts that intent into an explicit delegation policy and coordinates six fictional services through structured WebMCP tools.
A better human-agent relationship
Low-risk changes run in order. Actions outside the policy are refused. When Wavelength proposes a broadband transfer that raises the monthly price from £36 to £42, RELAY stops at a visible human checkpoint. The person reviews the exact provider, action, plan, price, contract, date, and one-use scope before approving.
Every successful mutation creates an append-only receipt. Rejected actions create separate refusal evidence proving that provider state did not change. The result is useful automation without unlimited authority.
Why WebMCP
Conventional browser automation guesses from pixels and page structure. RELAY instead exposes 27 focused tools through document.modelContext. An agent can inspect the move plan, read permissions, preview provider effects, execute allowed changes, request a human decision, retrieve receipts, and run controlled safety challenges through structured inputs and outputs.
The agent and visible interface share the same browser-local domain state. Mutations pass through the same policy regardless of whether they originate from the interface or a WebMCP call.
High-risk internet-plan changes require an exact, unexpired, single-use approval grant bound to the provider, action, proposal, plan, price, contract, move date, and postcode. Changed terms, replay, expiry, wrong-provider use, wrong-action use, and out-of-order actions are refused before mutation.
What people and agents can do together
A person can express one outcome and its boundaries once. An agent can coordinate the dependent work across multiple service surfaces, stop for a precise decision, resume with narrowly scoped authority, and return a coherent record of what changed.
This preview → policy → human approval → scoped commit → receipt pattern can extend beyond moving home to starting university, changing jobs, travel, government services, financial administration, and other multi-provider workflows.
Key features
- Six fictional service providers sharing one move plan
- 27 structured WebMCP tools on the main workspace
- Standalone WebMCP surfaces for provider sites
- Explicit allow, ask, and never-change delegation boundaries
- Preview-before-commit mutations
- Exact human approval for a recurring price increase
- Ten-minute, single-use, replay-safe approval grants
- Six append-only action receipts
- Five executable adversarial safety challenges
- Visible activity trace with tool names, scoped inputs, results, and receipt IDs
- Responsive, accessible mission-control interface
Implementation
RELAY uses Next.js, React, TypeScript, Vinext, and ChatGPT Sites. The shared domain layer owns the move plan, service ordering, policy decisions, approval grants, receipts, and refusals. A dedicated tool-definition layer exposes testable WebMCP contracts, while the registration lifecycle registers and unregisters them through document.modelContext.
The main workspace and provider pages use the same browser-local fictional service ledger, preventing human actions, agent actions, receipts, and visible state from drifting into separate demonstrations.
Verification
The release includes 29 automated tests, ten isolated tool-driven rehearsals, ten production-interface rehearsals, a five-image evidence set, and a narrated 2:47 public demonstration. Lint and production builds pass, the production dependency audit reports zero vulnerabilities, and the public app, repository, and video have all been verified without private-session access.
All displayed people, addresses, providers, accounts, and transactions are fictional. No credentials are required.
Links
- Live app: https://relay-webmcp.creamy-ibex-1200.chatgpt.site/
- Public source: https://github.com/ICY0U/relay-webmcp
- Demonstration: https://youtu.be/A_jYs6DvWWw
Built With
- chatgpt-sites
- next.js
- react
- typescript
- vinext
- vitest
- webmcp