Built-In Message Families

R2Kernel message specs define payload datatypes. They do not carry the transport envelope.

Ownership Rule

Information	Owner
payload fields and physical values	msg.* schema
endpoint kind, frame policy, and timing requirements	api.* contract
observed, published, and received timestamps	Event envelope
generated, sent, execute, valid-until, dispatch, sample, completion, response, and lateness timestamps	Control envelope

Do not create blanket StampedPose, StampedTwist, or similar public types. Use a pure spatial type when the API fixes the frame. Put a frame identifier in the owning domain message only when it is genuinely dynamic.

Payload timestamps remain appropriate for multi-time batches, trajectories, historical queries, and raw device-clock samples. These represent domain data, not transport lifecycle.

Family Map

Family	Responsibility
msg.core.common.primitive.v1	named scalar wrappers, empty requests, channel values, durations, and explicit domain timestamps
msg.core.spatial.v1	pure pose, twist, wrench, acceleration, inertia, and spatial math
msg.core.kinematics.v1	joint values, commands, and articulated state
msg.core.linalg.v1	vectors and matrices used by robotics payloads
msg.core.diagnostics.v1	public diagnostic observations
msg.actuator.*	low-level drive and servo payloads
msg.motion.*	articulated and manipulator motion payloads
msg.locomotion.*	body motion, mobile-base, odometry, and legged payloads
msg.sensor.*	sensor calibration and samples
msg.r2kernel.control.v1	public Control-cycle generation, ordering, intent, and state revision
msg.r2kernel.stream.v1	stream identity, codec profile, sample lifetime, transfer chunks, and bounded resource limits
msg.r2kernel.visual.v1, msg.r2kernel.depth.v1	typed visual and depth raster formats and transfer parts
msg.r2kernel.sensor.camera.v1, msg.r2kernel.sensor.rgbd.v1	camera calibration, camera source cycles, and paired RGB-D samples
msg.r2kernel.sensor.radar.v1	time-stamped rotating sectors, sensor returns, and source cycles without tracked object IDs
msg.r2kernel.sensor.lidar.v1, msg.r2kernel.sensor.pointcloud.v1	native scan/point layouts, samples, and source cycles
msg.localization.*, msg.mapping.*, msg.navigation.*	estimation and autonomous motion products
msg.perception.*	perception queries, detections, and streams
msg.capability.*	app-facing capability request and result payloads

Runtime transport and execution-envelope schemas remain private kernel implementation details. Public ControlCycle is domain metadata for the versioned APIs that opt in; it does not expose or replace runtime request IDs, transport timestamps, or execution reports.

IO Note

Digital and analog I/O contracts reuse indexed primitive wrappers. Input and output APIs are separate because a physical device may support only one direction.

Full Inventory

See the generated Message Index for every message and field.