oxbshw/Agent-Span ? reverse-engineered prompt

Build me a self hosted web access gateway for AI agents that can read and search content from lots of online platforms through one API.

I want the backend in Rust, fast and async, with cached access, automatic backend failover when a source breaks, and support for REST, SSE, and MCP so tools like Claude Code and Cursor can use it easily. It should include a command line app, installable SDKs, and a simple web dashboard that shows the health of each channel, performance stats, and a searchable list of supported sources.

Make it feel polished and production ready, with multi tenant support, basic access control, rate limiting, and audit logs. Include Docker support and clear startup instructions so I can run the whole thing locally. If anything depends on current library docs or best practices, look them up online and keep the implementation clean and practical.