Capture invocation payloads

Goal: See argument values on INVOKE rows in the Event Monitor log.

Prerequisites: Event Monitor installed; Play Mode; ILPP instrumentation active for the invocation site (or manual tagging — below).

Enable payload capture

1. Open Window → Event Monitor.
2. Toggle Payload (toolbar) on.

When enabled, the IL-instrumented path records invocation values and parameter names into the ring buffer. Names come from call-site locals (when PDB/debug symbols are available), then from delegate Invoke metadata, then fall back to value / arg0, arg1, …

The Log tab shows payloads as JSON, e.g. { "id": "Goblin" } instead of a bare string.

Note: Action<T> / Func<T> delegate metadata often names the parameter obj. For clearer names (damage, enemyId), use a custom delegate with named parameters, or ensure debug symbols are available so call-site local names are captured.

Warning — Performance and safety: Payload capture increases allocations (including boxing for value types) and log size. Keep it off during normal profiling unless you need arguments. Payload Details (reflection) is heavier still — use only for focused debugging.

Optional: TagPayload before firing

For patterns not covered by automatic injection, or when you need explicit control, call EventBus.TagPayload(...) immediately before invoking the event:

using EventMonitor.Runtime;

EventBus.TagPayload(damage, remainingHp, source);
OnDamaged?.Invoke(damage, remainingHp, source);

For explicit names in custom dispatch flows:

EventBus.TagPayloadWithNames(
    new[] { "damage", "remainingHp", "source" },
    new object[] { damage, remainingHp, source });
OnDamaged?.Invoke(damage, remainingHp, source);

Tagging is respected when payload capture is enabled and recording is on.

Payload details (reflection)

Enable Payload Details to inspect public fields/properties on payload objects (with safe limits: item count, depth, cycle detection). Use sparingly.

See also

• IL patterns and limitations
• EventBus API