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.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-only state and timing schemas are internal to runtime/core. They are not available as public dictionary payloads.

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.