Examples verify encoding, not reusable randomness
Key establishment includes nonces, server identity and DH-parameter checks. Intermediate values in examples are test vectors, not production material to reuse. Follow field-specific byte order rather than reversing an entire payload.
Framing differs from the underlying connection
Abridged, Intermediate, Padded intermediate and Full are MTProto framing schemes. TCP and WebSocket are transports. WebSocket frame boundaries do not define MTProto message boundaries. Respect configured addresses and ports.
Implementation recommendations
Prefer a maintained library. For protocol research, use official vectors offline and test truncation, combined frames, invalid lengths and disconnects. Bound buffers before allocating from network-provided lengths.
Stop on failed security checks and retain sanitized reasons. Do not maintain connectivity by disabling verification or accepting malformed key exchanges.