Reltio MCP Server – Developer Edition is a lightweight, plugin-based MCP server designed to enable language-model-assisted entity matching within Reltio environments. It exposes an extensive set of MCP tools that empower developers to query, inspect, and modify Reltio data as part of a unified workflow. Core capabilities include searching entities with advanced filtering, retrieving detailed entity information, updating attributes, and supporting iteration over potential matches. The server also provides merge and reconciliation support, with tools to merge entities, export merge trees, and mark non-matches. Designed for development and testing, it can be run with or without Docker and is configured via a .env file (server name, environment, client credentials, tenant, and auth server). It can be integrated with Claude Desktop App or custom MCP clients (OpenAI, Gemini, etc.) through CLI clients or programmatic interfaces. Setup scripts, installation commands, and a comprehensive test suite are included. An Agent Client enables OAuth-based access to the MCP server for interactive querying. The Developer Edition emphasizes extensibility and tooling to build language-model-powered entity matching within Reltio ecosystems.