Unihand is a standalone server application for character information in the Unicode Han Database, published by the Unicode Consortium.
Links:
Compiling this application requires a recent version of the Go programming language. With it, run:
go build cmd/server/server.go
Download the Unihan.zip file to your local system. After compiling, run a local server with this command:
cmd/server/server -zip /path/to/Unihan.zip -listen :8978
This will open a local HTTP server on port 8978. Query it by sending it HTTP requests like this:
curl http://localhost:8978/char/91CF
This will provide information on Unicode character U+91CF.
UNIHANd and its source code are available under the terms of the BSD 3-clause license. Find out what that means here: https://www.tldrlegal.com/l/bsd3
The Unihan dataset is published by the Unicode Consortium under certain terms and conditions. Read about them here: https://www.unicode.org/copyright.html