neuron-monitoring

Neuron AI Monitoring

This skill helps you debug and monitor Neuron AI applications using the framework's event-driven observability system.

The progression is always the same: components emit events → you subscribe listeners. A LogListener writing to stdout and a custom tracing listener are the same mechanism, differing only in where the events go.

Event System Observability

Neuron uses a PSR-14 event dispatcher owned by each Workflow/Agent instance for monitoring all framework events. There is no global state: listeners are registered on the instance and observe every run of it.

Event Emission

All components emit event objects automatically. Every event class extends NeuronAI\Observability\ObservabilityEvent and lives in the Observability namespace of the module that emits it:

// NeuronAI\Workflow\Observability — the lifecycle, emitted by the workflow engine:
// WorkflowStart, WorkflowEnd, WorkflowNodeStart, WorkflowNodeEnd,
// MiddlewareStart, MiddlewareEnd, BranchStart, BranchEnd, ChannelError,
// WorkflowInterrupted (run paused for external input), WorkflowError (failure)
//
// NeuronAI\Agent\Observability — emitted by agent nodes:
// InferenceStart, InferenceStop, ToolCalling, ToolCalled,
// MessageSaving, MessageSaved, SchemaGeneration, SchemaGenerated,
// Extracting, Extracted, Deserializing, Deserialized, Validating, Validated
//
// NeuronAI\RAG\Observability — emitted by RAG nodes:
// Retrieving, Retrieved, PreProcessing, PreProcessed, PostProcessing, PostProcessed

Each event carries its own data plus the emission context stamped by the framework: ->source (the emitting component), ->execution (the run identity) and ->branchId (the parallel branch, or null). ->name() returns the string name ('inference-start') and ->toArray() the event's own data.

Every node and middleware start is followed by its end, whatever the outcome: WorkflowNodeEnd and MiddlewareEnd carry ->outcome, a NodeOutcome (Completed, Suspended or Failed), so a span can be closed and marked as soon as its node ends.