# PropXchain

> PropXchain (propxchain.com, PropXchain Ltd, UK Companies House 17018978) is a UK online platform for selling or buying a home. It coordinates the conveyancing process on one shared record, so the seller, buyer, conveyancer and estate agent see the same live view of the transaction. PropXchain is free to use for buyers and sellers: no plans, no tiers, no platform fee. Third-party items are paid per item, priced when you order: property searches, ID and AML checks, the GBP 7 HM Land Registry title pull and the GBP 25 property chain check. Conveyancers quote directly. PropXchain has a live, hosted MCP server at https://mcp.propxchain.com/mcp that any MCP client (claude.ai, Claude Desktop, Claude Code, ChatGPT, Cursor) can add as a custom connector.

Not to be confused with Propchain (PROPC), an unrelated crypto token and real-estate tokenisation project. PropXchain has no token, no coin and no ICO; it records SHA-256 hashes of transaction milestones on the Internet Computer (ICP) blockchain, and users pay no gas fees.

- Production: https://propxchain.com
- Status: pre-launch, open for waitlist sign-ups at https://propxchain.com/#notify
- Contact: info@propxchain.com

## Connect an AI assistant (MCP)

PropXchain is MCP-native. Every transaction a user can see in the web app can also be read and progressed by their AI assistant through the Model Context Protocol.

- MCP server URL: https://mcp.propxchain.com/mcp (Streamable HTTP, OAuth 2.1)
- claude.ai or Claude Desktop: Settings, Connectors, Add custom connector, paste the URL above, leave client ID and secret blank. Approve with your PropXchain email and the 6-digit code sent to it.
- Claude Code: `claude mcp add --transport http propxchain https://mcp.propxchain.com/mcp`
- Other MCP clients: add a remote (Streamable HTTP) server with the URL above. The client discovers the authorization server from the 401 challenge (RFC 9728 protected resource metadata, RFC 8414 authorization server metadata, PKCE S256, Client ID Metadata Documents).
- Access is per transaction: the user gives the assistant a TX-XXXX-XXXX invite code and it calls `propxchain_join_transaction_as_bot`. Any party can remove the assistant from the transaction's bot panel. Money and legal steps still stop at a human consent checkpoint.
- Tools (19): propxchain_join_transaction_as_bot, propxchain_join_transaction, propxchain_list_my_transactions, propxchain_search_transactions, propxchain_get_transaction, propxchain_get_status, propxchain_next_step, propxchain_get_transaction_chain, propxchain_create_transaction, propxchain_get_checklist, propxchain_update_checklist, propxchain_list_documents, propxchain_upload_document, propxchain_verify_document, propxchain_get_audit_trail, propxchain_get_property_intel, propxchain_explain_process, propxchain_send_message, propxchain_list_connected_bots
- [Human setup guide](https://propxchain.com/agent): Step-by-step connection guide with copy-paste prompts
- [Agent authorization (auth.md)](https://propxchain.com/auth.md): OAuth 2.1 discovery, tokens and errors
- [MCP manifest](https://propxchain.com/.well-known/mcp.json): Machine-readable server card
- [Agent catalog](https://propxchain.com/.well-known/ai-catalog.json): Agentic Resource Discovery manifest (MCP server, A2A card, agent skills)
- [Local stdio server](https://www.npmjs.com/package/@propxchain/mcp-server): `npm install -g @propxchain/mcp-server` for hosts without remote MCP support; source at https://github.com/Madhatt4/propxchain-mcp-server

## Docs

- [Full Documentation](https://propxchain.com/llms-full.txt): Extended AI-readable reference (canister APIs, lifecycle, roles, MCP tools)
- [Resources](https://propxchain.com/resources): Plain-English guides for buyers and sellers

## Key Features

- 2-phase transaction creation wizard (property details then transaction details)
- Invite code system (TX-XXXX-XXXX) for parties to join transactions
- Transaction lifecycle: active, exchanged, completion_initiated, blockchain_completed, land_registry_registered
- GDPR-compliant document storage (SHA-256 hash on-chain, files stay local)
- Solicitor document verification via hash comparison
- Property intelligence via Land Registry API, Environment Agency flood data, Historic England heritage checks, and local authority planning data
- Oscar AI assistant for guided conveyancing and document analysis
- Role-based access control across 18 user types
- Internet Identity authentication (no passwords, blockchain-native)
- Legal forms: TA6 (Property Information), TA7 (Leasehold), TA10 (Fixtures and Fittings)
- Contract exchange with dual solicitor signing
- In-app messaging between transaction parties
- Firm management

## Canister Architecture

Canisters deployed on IC mainnet:

- Core (`3tv4o-xiaaa-aaaaa-qedaa-cai`): Core platform services
- Frontend (`lzpic-oaaaa-aaaaa-qcwva-cai`): React application asset canister
- Property Registry (`l6oow-dyaaa-aaaaa-qcwvq-cai`): Property blockchain records and ownership
- Document Verification (`xand7-wiaaa-aaaah-arlea-cai`): Solicitor document verification tracking
- Document Storage (`646az-pqaaa-aaaaa-qczja-cai`): Hash-only document proofs (GDPR compliant)
- Transaction Manager (`llj73-cqaaa-aaaaa-qcwwa-cai`): Transaction lifecycle and contract exchange
- User Management (`lmizp-piaaa-aaaaa-qcwwq-cai`): User profiles, roles, and audit logs
- Email Service (`5by6v-qyaaa-aaaaa-qc65a-cai`): Notification delivery
- Firm Factory (`gcqvm-tiaaa-aaaaa-qdszq-cai`): Law firm management
- Ledger Manager (`hty74-maaaa-aaaaa-qcxza-cai`): Financial and analytics tracking
- Message Manager (`37una-maaaa-aaaaa-qd3mq-cai`): In-app messaging between parties
- Oscar Canister (`khstc-3qaaa-aaaaa-qdyfq-cai`): AI assistant backend
- Land Registry (`o4flv-xaaaa-aaaaa-qdaeq-cai`): UK Land Registry integration

## Tech Stack

- Frontend: React, TypeScript, Vite, TailwindCSS
- Backend: Motoko (ICP canisters)
- Blockchain: Internet Computer Protocol (IC mainnet)
- Authentication: Internet Identity
- AI: Anthropic Claude (Oscar assistant)

## Optional

- Web app source: https://github.com/Madhatt4/propxchain-consumer
- MCP server source: https://github.com/Madhatt4/propxchain-mcp-server
- Contact: info@propxchain.com