"OpenAI's Web Retrieval Infrastructure" matching MCP connectors:

MCP server for Project Gutenberg — 75,000+ public-domain ebooks with full plain-text retrieval.

MusicBrainz MCP — wraps MusicBrainz Web Service v2 (free, no auth)

The world's cultural intelligence infrastructure layer. Kultur.dev gives every AI agent, coding assistant, and enterprise platform the ability to understand 195 countries' cultural norms, geopolitical sensitivities, and business etiquette. 11 MCP tools including cultural context analysis, Hofstede 6-D scoring, geopolitical heatmaps, content localization, holiday calendars, and adaptive risk scoring powered by a 645K+ document knowledge base. Essential for any AI building products, content, or co