Registry Server

The PKP Registry Server aggregates multiple PKP catalogs for global product discovery.

Installation

npm install -g @pkprotocol/registry-server

Usage

pkp-registry-server [options]

In-Memory Storage (default)

pkp-registry-server --domain pkp.kodda.ai

PostgreSQL Storage

For production use with persistence and full-text search:

pkp-registry-server --storage postgresql \
  --pg-host localhost \
  --pg-database pkp \
  --pg-user pkp \
  --domain pkp.kodda.ai

PostgreSQL Options:

Option	Description
--storage postgresql	Enable PostgreSQL storage
--pg-host <host>	PostgreSQL host (default: localhost)
--pg-port <port>	PostgreSQL port (default: 5432)
--pg-database <db>	Database name (required)
--pg-user <user>	Database user (required)
--pg-password <pass>	Database password
--pg-ssl	Enable SSL connection

Environment Variables:

export PGHOST=localhost
export PGPORT=5432
export PGDATABASE=pkp
export PGUSER=pkp
export PGPASSWORD=secret

Database Setup

Run migrations before using PostgreSQL:

psql -d pkp -f migrations/001_create_pkp_domains.sql
psql -d pkp -f migrations/002_create_pkp_registry_index.sql
psql -d pkp -f migrations/003_create_pkp_query_log.sql
psql -d pkp -f migrations/004_create_fulltext_search_pt.sql

MCP Configuration

{
  "mcpServers": {
    "pkp-registry": {
      "command": "pkp-registry-server",
      "args": ["--domain", "registry.pkp.dev"]
    }
  }
}

Tools

search_products

Search products across all registered catalogs.

{
  query?: string,
  category?: string,
  brand?: string,
  domain?: string,      // Filter by catalog domain
  min_price?: number,
  max_price?: number,
  limit?: number
}

resolve_product

Resolve a PKP URI to product details.

{
  uri: string  // e.g., "pkp://store.example.com/iphone-16-pro"
}

register_catalog

Register a new catalog in the registry.

{
  domain: string  // Domain hosting the catalog
}

refresh_catalog

Re-crawl and update a registered catalog.

{
  domain: string
}

unregister_catalog

Remove a catalog from the registry.

{
  domain: string
}

list_catalogs

List all registered catalogs.

list_categories

List all categories across catalogs.

get_registry_stats

Get registry statistics (catalog count, product count, etc).

compare_across_catalogs

Compare products from different catalogs.

{
  uris: string[]  // Array of PKP URIs
}

Resources

pkp://registry/stats

Registry statistics.

pkp://registry/catalogs

List of registered catalogs.

Product URIs

The registry uses PKP URIs for global product identification:

pkp://{domain}/{sku}

Examples:

• pkp://apple.com/iphone-16-pro
• pkp://samsung.com/galaxy-s25-ultra
• pkp://store.example.com/my-product

Catalog Discovery

The registry discovers catalogs by fetching:

https://{domain}/.well-known/pkp/catalog.json

Catalogs must follow the PKP specification to be indexed.