LCSH Recommendation Tool

LCSH Recommendation Tool helps catalogers and librarians assign Library of Congress Subject Headings (LCSH) to bibliographic records using AI. Powered by Google's Gemini 2.5 Flash, the extension analyzes bibliographic information — title, author, abstract, table of contents, and even images of book covers or title pages — and recommends validated LCSH headings with MARC records ready to use. Want a standalone web app instead? Try the LCSH Cataloging Assistant at https://assistant.cataloguer.name — a full-featured Progressive Web App (PWA) that supports multiple AI providers, works offline, and requires no installation. Visit https://cataloguer.name for tutorials, setup guides, and documentation for all our cataloging tools. HOW IT WORKS 1. Enter your free Gemini API key (get one at ai.google.dev) 2. Provide bibliographic details about the work you're cataloging 3. Optionally upload images of book covers or title pages for additional context 4. The extension generates LCSH candidates using AI, then validates each one against the Library of Congress authority files at id.loc.gov 5. Review the validated recommendations, sorted by match confidence 6. Copy MARC 650 records or export results as CSV KEY FEATURES AI-Powered Suggestions: Generates LCSH candidates from bibliographic metadata and images using Gemini 2.5 Flash with multimodal capabilities. LOC Authority Validation: Every suggestion is checked against the Library of Congress Subject Headings and Name Authority File (LCNAF) via the official LOC suggest2 API. Similarity Scoring: Uses Levenshtein distance to measure how closely each AI suggestion matches an authorized LOC heading. Results are color-coded: green for strong matches, amber for moderate, red for weak. MARC Record Generation: Produces ready-to-use MARC 650 field records for validated headings, with correct indicators and subfields. One-click copy to clipboard. Image Analysis: Upload PNG or JPEG images of book covers, title pages, or other materials. The AI extracts additional bibliographic context to improve recommendations. Conversation History: All sessions are saved locally for reference. Browse, search, and manage your past cataloging sessions. PRIVACY All processing happens between your browser and the Gemini API. No data is sent to any other server. Your API key and conversation history are stored only in your browser's local storage. Images are sent directly to the Gemini API and are not stored anywhere else. GETTING STARTED You'll need a Google Gemini API key, which is available for free at ai.google.dev. Once installed, click the extension icon, enter your API key, and launch the tool. No account creation or sign-up required. For step-by-step setup instructions, video tutorials, and tips on getting the best results, visit https://cataloguer.name. ALSO AVAILABLE AS A WEB APP Prefer not to install an extension? The LCSH Cataloging Assistant PWA at https://assistant.cataloguer.name offers the same core functionality plus support for multiple AI providers, batch processing, and offline access. No installation needed — just open it in your browser. Built for catalogers, by catalogers. Visit https://cataloguer.name to learn more.