Traffic Model
Workflows And Traces
Workflows let Arc reason about multi-step runs instead of isolated requests. Traces and spans give you a single execution view across those calls.
Object Model
Workflow Model
Workflow
Defines execution policy such as budgets, duration, and enforcement mode.
Trace
One workflow execution identified by a trace ID.
Span / Call
Individual proxied requests or steps within a trace.
A workflow defines the policy. A trace is one execution inside that workflow. Each proxied call can become a span inside the trace.
Workflow Headers
X-Arc-Workflow
Workflow slug. If omitted, Arc can resolve the default active workflow for the project.
X-Arc-Trace-Id
Stable trace ID to continue an existing run or explicitly name a new one.
X-Arc-Span-Name
Human-readable name for the current span or call.
X-Arc-Parent-Span-Id
Optional parent relationship if you are constructing a tree of spans.
X-Arc-Trace-Status
Optional terminal status to close the trace when this request finishes.
Workflow Policy
Workflows can enforce budget caps, max duration, max calls per trace, and trace timeout. Arc evaluates these in the proxy path once workflow mode is active.
When to use workflows