Entity Detective

## Entity Detective **Entity Detective** is a server-side Fabric mod built for one job: find entity-related lag fast. One command tells you which entity types are costing the most MSPT, where lazy mobs are silently accumulating, and where persistent creatures will never despawn — across every loaded dimension at once, no client mod needed. Works in singleplayer without enabling cheats. --- ### What it does - **Hotspot scan** — Run a 20-tick sample across all dimensions and get back the top-5 most expensive entity types ranked by MSPT, with no arguments needed — a fast first pass when you don't know where to look. - **Lazy mob detection** — Pinpoint mobs stranded in chunks with no player within 128 blocks — the exact threshold Minecraft uses for despawn checks — where the server will never clean them up naturally - **Persistent mob detection** — Find name-tagged mobs, item-holders, leashed animals, and vehicle riders that will never despawn even when they do tick. - **MSPT profiling** — Measure how many milliseconds per tick any entity type is consuming, or profile every type at once sorted by cost, or just examine every entity inside a variable chunk range - **Chunk loader detection** — Server load is often caused by chunk loaders. Find them fast. List all active portal chunk loaders (paired OW ↔ Nether) and ender pearl stasis chambers across every dimension. - **Block entity ticking audit** — Use `--ticking-only` to find which block entities in a large farm actually ticked during an observation window, and `--debug` to see per-position tick counts instead of aggregate MSPT. - **Player profiling (`nark`)** — Measure the MSPT cost of all entity types in the 21×21 chunk range surrounding any online player, to find what's expensive near their location. --- ### Quality of life features - **Per-dimension summaries** — See every entity type sorted by count, one block per dimension, across overworld, nether, and end simultaneously - **Clickable teleport links** — Every chunk header and individual entity line is clickable in chat and pastes `/tp <playername> x y z` directly to the chunk centre or exact entity location - **Live mob cap** — Check current vs. maximum entities per category with colour-coded saturation so you can spot mob cap pressure at a glance - **Command alias** — Available as both `/entitydetective` and `/ed` --- ### Command structure ``` /entitydetective ├── mob <category> │ │ category: monster | creature | ambient | axolotls | water_creature | water_ambient │ │ (bare) — Type-count summary per dimension │ │ --lazy-only — Type-count table, non-persistent mobs in lazy chunks │ │ --persistent — Type-count table, persistent mobs only │ │ subtype: all | name-tagged | holding-item | structure-spawn | in-vehicle | leashed | custom │ │ --world <dim> — Scope to overworld | nether | end │ │ --range <chunks> — Scope to (2N+1)×(2N+1) chunk square (0 = single chunk) │ │ --detail — Expand to chunk-grouped entity list with clickable /tp links │ └── cap — Live mob cap (current vs max, colour-coded) │ ├── entity │ │ (bare) — Summary of all entity types by count, per dimension │ │ --lazy-only — Type-count table, non-persistent entities in lazy chunks │ │ --persistent — Type-count table, persistent entities only │ │ --world <dim> — Scope to a specific dimension │ │ --detail — Expand to chunk-grouped entity list with clickable /tp links │ ├── --range <chunks> — Instant census of every entity type within range (0 = single chunk; no tick window) │ ├── locate <type> — Locate any entity type (tab-complete from live world, substring match) │ │ --lazy-only, --world <dim>, --range <chunks>, --detail │ │ --ticking-only (block entities only) — filter to positions that actually ticked │ ├── profile <type> │ │ Measure MSPT cost over a tick window (default 100 ticks / 5 s; max 6 000 ticks / 5 min) │ │ --world <dim>, --range <chunks> │ │ --debug (block entities only) — per-position tick counts instead of aggregate MSPT │ └── profile all │ Profile every entity type simultaneously, sorted by MSPT cost descending │ (bare): all dimensions | --world <dim>: one dimension | --range <chunks>: local │ └── item │ (bare) — Dropped item summary per dimension, colour-coded by severity │ --lazy-only — Type-count table, lazy chunks only │ --world <dim> — Scope to a specific dimension │ --range <chunks> — Scope to chunk square around your position │ --detail — Expand to chunk-grouped item list with clickable /tp links └── locate <item_id> Find chunks with a specific item type (tab-complete, substring match) --lazy-only, --world <dim>, --range <chunks>, --detail chunks