// Package constants define constant variable
package constants

// Assuming the B3 specification
const (
	HeaderTraceID      = "X-B3-TraceId"
	HeaderSpanID       = "X-B3-SpanId"
	HeaderParentSpanID = "X-B3-ParentSpanId"
)

// traceCtxKey is an unexported type for context keys to avoid collisions with other packages.
type traceCtxKey string

// Typed context keys for trace values — use these with context.WithValue / ctx.Value.
var (
	CtxKeyTraceID      = traceCtxKey(HeaderTraceID)
	CtxKeySpanID       = traceCtxKey(HeaderSpanID)
	CtxKeyParentSpanID = traceCtxKey(HeaderParentSpanID)
)