MRP Overview

AppleTvControlLibrary.Mrp is a .NET client library for Apple TV's MRP (Media Remote Protocol), used to receive now-playing metadata (title, artist, album, artwork, playback position) and to send playback commands (play/pause, skip, volume). Apple TV no longer exposes MRP over a raw TCP socket; this library speaks MRP tunneled over an AirPlay 2 connection, matching pyatv's current transport.

The implementation is scoped to MRP-over-AirPlay. It does not implement Companion Link, AirPlay 2 media/audio/video streaming, RAOP, or DMAP/DACP.

Packages

Package	Purpose
AppleTvControlLibrary.Mrp	MRP protocol, AirPlay 2 tunnel, protobuf messages, player/queue state tracking, and high-level commands.
AppleTv.Hap (shared, not separately packaged for MRP)	HAP pair-setup/pair-verify and ChaCha20-Poly1305 crypto, shared with the Companion Link library.

Relationship to Companion Link

Companion Link and MRP are separate tvOS protocols with different responsibilities: Companion Link carries HID input, touch, and coarse media/volume/power control; MRP carries rich now-playing metadata and fine-grained playback control. A host application that wants both remote input and now-playing UI typically pairs and connects to both protocols independently - see src/AppleTv.Remote.Mrp.Wpf and src/AppleTv.Remote.Wpf for separate reference hosts, one per protocol.

Protocol formats

MRP messages are length-prefixed Protocol Buffers frames (ProtocolMessage), not OPACK. Protocol Buffers ("protobuf") is Google's language-neutral binary serialization format; MRP's message schemas are compiled from .proto files into the generated types under AppleTvControlLibrary.Mrp.Protobuf. Pairing and verification reuse the same HAP TLV8 messages and SRP/Ed25519/X25519 primitives as Companion Link, via the shared AppleTv.Hap library.

See the MRP API reference.