A NeoForge mod that instruments a Minecraft server with OpenTelemetry, exporting metrics via OTLP to any compatible collector (Prometheus, Grafana Alloy, OpenTelemetry Collector, Dynatrace, etc.).

Metrics

Metric	Description
TPS & tick time	Server ticks per second and mean tick duration
Player count & latency	Online player count and per-player network latency
Chunk counts	Loaded chunk counts per dimension
Entity counts	Entity counts per dimension
Block entity counts	Block entity counts per dimension
Item entity counts	Item entity (dropped item) counts per dimension
World save duration	Histogram of world save time per dimension
Scheduled tick queue	Block and fluid scheduled tick queue sizes per dimension
Chunk generation	Counter of newly generated chunks
JVM metrics	Heap/non-heap memory, GC, threads, classes

Requirements

• Minecraft 26.1.2 with NeoForge 26.1.2.71+
• Java 21
• A running OTLP-compatible metrics endpoint

Primarily tested with the OpenTelemetry Collector (contrib) + Prometheus + Grafana stack. Other OTLP receivers (Grafana Alloy, Dynatrace, etc.) should work but are less tested.

Installation

1. Download the latest JAR from Releases and drop it in your server's mods/ folder.
2. Start the server once to generate the config file at config/tracebullet-server.toml.
3. Set otel.url to your collector's OTLP endpoint and restart.

Configuration

The config file is generated at config/tracebullet-server.toml on first launch.

OTel settings

Key	Default	Description
otel.url	""	OTLP endpoint URL (required to export anything)
otel.auth	""	Authorization header value — must start with Bearer or Basic
otel.service_name_override	""	Override service.name; defaults to the current world name
otel.custom_attributes	[]	Extra resource attributes in key=value format

Threading

Key	Default	Description
threading.schedule_thread_pool_size	availableProcessors × 0.25	Background thread pool size (1–32)

Metric toggles

Each metric group can be individually enabled or disabled. All default to true.

Key	Controls
metrics.tps	TPS and tick time
metrics.player	Player count and latency
metrics.world_chunk	Chunk counts per dimension
metrics.entity	Entity counts per dimension
metrics.block_entity	Block entity counts per dimension
metrics.item_entity	Item entity counts per dimension
metrics.world_save	World save duration histogram
metrics.scheduled_tick	Scheduled tick queue sizes
metrics.chunk_generation	Chunk generation counter
metrics.jvm	JVM memory, GC, threads

Building from source

./gradlew build

The output JAR is placed in build/libs/.

License

MIT — see LICENSE.