retractionwatch-mcp: A Model Context Protocol Server for Research-Integrity Verification via Crossref's Retraction Watch Database

We present retractionwatch-mcp, an open-source Model Context Protocol (MCP) server that exposes the Retraction Watch database to language-model agents via Crossref's CC-BY 4.0 redistribution of the registry. Existing scholarly-metadata MCP servers (arXiv, Semantic Scholar, Crossref, OpenReview) do not surface retraction status, leaving citation generation by LLM agents vulnerable to a silent failure mode: confidently citing a retracted paper. retractionwatch-mcp closes this gap with six MCP tools covering single-DOI checks, batch screening, search, recent-retraction feeds, and author-level integrity checks. We validate the server end-to-end against the canonical Wakefield 1998 retraction. The package is available as pip install retractionwatch-mcp at github.com/OpenCodice-Research/retractionwatch-mcp. OpenCódice Technical Report OC-TR-2026-008.