The `webcrypto-core` library provides a common input validation layer for WebCrypto polyfills, designed to be used by various WebCrypto implementations like `node-webcrypto-ossl`, `node-webcrypto-p11`, and `webcrypto-liner`. It is primarily intended for developers creating their own WebCrypto polyfills, offering a structured way to implement cryptographic algorithms and validate inputs. The library includes examples and tools to help build custom WebCrypt interfaces, making it a niche but essential resource for advanced cryptographic development.