Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add chapmanjw/minecraft-java-fabric-claude-plugin/plugin install minecraft-javaWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/chapmanjw/minecraft-java-fabric-claude-plugin/terrain-cave)<a href="https://agentmods.dev/skills/chapmanjw/minecraft-java-fabric-claude-plugin/terrain-cave"><img src="https://agentmods.dev/badge/skills/chapmanjw/minecraft-java-fabric-claude-plugin/terrain-cave.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00107 | $0.00734 |
| Opus 5 | $0.00053 | $0.00367 |
| Sonnet 5 | $0.00021 | $0.00147 |
| Haiku 4.5 | $0.00011 | $0.00073 |
Grade A, and why
terrain-cave scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.
terrain-cave (Tier-3 leaf)
You design deliberate underground space — not noise the player stumbles into,
but a void with intent: a known entrance, a route, chambers sized for a purpose,
and a material story. You are a forked leaf authoring a recipe + carve/dress
phases. Read ${CLAUDE_PLUGIN_ROOT}/reference/terrain/caves.md (your method) and
toolkit-api.md.
Method
- Plan the space. Entrance, route, chamber sizes/purposes, the material story
(stone type, ores, dripstone, water). For a cave base, size the chamber for
the build it will host and hand the floor+walls to
build-structure. - Carve the void (anisotropic 3D noise threshold).
- Cheese caverns (wide, rounded): sample 3D noise at
(x*0.5, y, z*0.5), carveairwherenoise < ~-0.3, damped near the surface. - Ravines (tall, thin): sample at
(3x, 0.4y, 3z), carve wherenoise < ~-1.3with a log depth filter. - Tubes/passages: swept circular cross-section along a
Centerlineroute. Emit asairfills viablock_fill_region(hollow) /block_fill_batch— tile manually under the 32,768 cap;block_replace_in_regiondoes NOT auto-tile.
- Cheese caverns (wide, rounded): sample 3D noise at
- Structural safety. Leave pillars/thick ceilings over wide spans; vary ceiling height; never carve into a fluid body without a plan (check the survey); plan lighting as part of the build, not after.
- Dress the void. Strata on the walls (deepslate below y0); features via
level_place_feature(dripstone_cluster,pointed_dripstone,glow_lichen,cave_vine,moss_patch,amethyst_geode) mask-gated (lichen on walls, dripstone on ceiling, moss in damp/low areas); water/lava features along the route.
Non-negotiables / quality_contract
No flat 30-block ceilings (vary + pillar them); support present over spans; the
space is lit; no unintended fluid breach. Runs through GATE A (verify) and
exec-inspect like any terrain. If the cave hosts a build, ground it with
terrain-integrate so it sits in the cave, not in a box carved out of it.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 7d ago First seen · 53 lines · 107 tokens per session scan A b4cbbe0735b8
terrain-cave is a skill published in the GitHub repository chapmanjw/minecraft-java-fabric-claude-plugin (6 stars, last pushed 10d ago), licensed MIT. It adds 107 tokens to every session and 734 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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