Crate agent_kernel 

Agent lifecycle state machine and execution loop.

This crate provides the building blocks required by MXP-native agents: lifecycle management, message routing, and a lightweight scheduler backed by tokio.

Structs

AgentKernel

Core runtime that wires lifecycle, scheduler, and MXP handlers.

AgentRecord

Snapshot of an agent returned by discovery calls.

CallExecutor

Executes MXP Call messages by invoking registered tools and the configured ModelAdapter.

CallOutcome

Outcome of processing a call message.

CheckpointMetadata

Metadata about a checkpoint.

CollectingSink

Sink used during testing to capture outcomes.

CompositeAuditEmitter

Fan-out emitter that broadcasts audit events to multiple sinks.

CompositePolicyObserver

Composite observer that forwards decisions to a collection of observers.

DiscoverRequest

Agent discovery request payload.

DiscoverResponse

Discovery response payload.

ErrorResponse

Error payload used for protocol error responses.

GovernanceAuditEmitter

Sends audit events to a remote governance agent using MXP transport.

HandlerContext

Context provided to message handlers.

HeartbeatRequest

Heartbeat request emitted by agents.

HeartbeatResponse

Heartbeat acknowledgement returned to agents.

KernelMessageHandler

Handler implementation that wires the call executor into the MXP handler trait.

KernelMessageHandlerBuilder

Builder for KernelMessageHandler that automates tool registration and optional components.

Lifecycle

Lifecycle state manager.

MxpAuditObserver

Observer that emits MXP audit events for deny/escalate outcomes.

MxpRegistryClient

MXP-backed registry client that speaks directly to the MXP Nexus registry service.

RegisterRequest

Registration payload emitted by agents.

RegisterResponse

Successful registration acknowledgement.

RegistrationConfig

Configuration for registration and heartbeat maintenance.

SchedulerConfig

Maximum number of concurrent tasks allowed per agent.

ShutdownCoordinator

Coordinates graceful shutdown of agent workloads.

StateCheckpoint

Checkpoint containing critical agent state for recovery.

StateRecovery

Manages checkpoint persistence and recovery.

TaskScheduler

Lightweight wrapper around tokio::spawn that enforces per-agent concurrency.

ToolInvocationResult

Result describing an executed tool invocation.

TracingAuditEmitter

Tracing-based audit emitter that logs MXP audit events.

TracingCallSink

Sink implementation that logs to tracing.

TracingPolicyObserver

Observer that emits decisions to the tracing system.

ValidationConfig

Configuration for message validation.

WorkGuard

RAII guard for tracking in-flight work.

Enums

AgentState

Discretely states an agent can occupy during its lifetime.

HandlerError

Errors that can occur during message handling.

KernelError

Errors emitted by AgentKernel operations.

LifecycleError

Errors emitted by the lifecycle controller.

LifecycleEvent

Events that trigger lifecycle transitions.

RecoveryError

Errors from state recovery operations.

RegistryError

Errors surfaced by registry integration.

SchedulerError

Errors produced by the scheduler.

ShutdownError

Errors from shutdown operations.

ShutdownState

Shutdown state enumeration.

ValidationError

Errors that can occur during message validation.

WireAgentStatus

Simplified agent status representation.

Traits

AgentMessageHandler

Trait implemented by agent-specific MXP message handlers.

AgentRegistry

Trait implemented by discovery/registry backends.

AuditEmitter

Emits MXP audit events when policy decisions deny or escalate requests.

CallOutcomeSink

Observer trait used to capture call outcomes (for logging, metrics, etc.).

PolicyObserver

Observer invoked whenever a policy decision is produced.

Functions

validate_message

Validates an MXP message against configured limits.

Type Aliases

HandlerResult

Result alias for handler operations.

KernelResult

Result alias for kernel operations.

LifecycleResult

Result alias used for lifecycle operations.

RecoveryResult

Result type for recovery operations.

RegistryResult

Result alias for registry operations.

SchedulerResult

Result alias for scheduler operations.

ShutdownResult

Result type for shutdown operations.

ValidationResult

Result alias for validation operations.