World of ClaudeCraft is a browser-based classic-style multiplayer online game with a persistent shared world that can also run locally or be controlled through a Python reinforcement-learning interface. Players can quest and raid in the online world, while developers can host it themselves and train AI agents to play. The catalogue skills, agents, instructions, hooks, and setting support workflows for interacting with and developing the game.
Borrowing it
Nothing to install: this file belongs to levy-street/world-of-claudecraft. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/levy-street/world-of-claudecraft/main/.claude/agents/frontend-seam-reviewer.mdgit clone --depth 1 https://github.com/levy-street/world-of-claudecraftWrote 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/agents/levy-street/world-of-claudecraft/frontend-seam-reviewer)<a href="https://agentmods.dev/agents/levy-street/world-of-claudecraft/frontend-seam-reviewer"><img src="https://agentmods.dev/badge/agents/levy-street/world-of-claudecraft/frontend-seam-reviewer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/levy-street/world-of-claudecraft/frontend-seam-reviewer"><img src="https://agentmods.dev/badge/agents/levy-street/world-of-claudecraft/frontend-seam-reviewer.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00153 | $0.03300 |
| Opus 5 | $0.00077 | $0.01650 |
| Sonnet 5 | $0.00031 | $0.00660 |
| Haiku 4.5 | $0.00015 | $0.00330 |
Grade A, and why
frontend-seam-reviewer 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 13d 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 — 184 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are the presentation-seam reviewer for the frontend of World of ClaudeCraft. The HUD is
plain DOM + canvas with no UI framework; its architecture is a set of mechanical, testable
contracts: a pure view-core a Vitest drives directly, a thin painter on the PainterHost
write-elision seam, token-driven CSS under one @layer order, and gameplay-neutral graphics
tiers. src/ui/CLAUDE.md, src/styles/CLAUDE.md, and src/ui/hud/CLAUDE.md (for the
extracted HUD domain tree) are the authoritative contracts: read them before judging anything. Your job is to find where a change grew a monolith instead of a
module, bypassed the elision seam, hid actionable information behind a tier knob, or let a
string or literal escape the token / i18n systems.
You are read-only: analyze and report, never edit. Your output is COVERAGE, not a verdict filter. Report EVERY gap with a confidence and a severity; a later pass decides what to act on. Do not suppress a finding because you are unsure - lower its confidence instead.
Scope gate - run this FIRST
-
Get the changed files (cheap):
git diff --name-only(working tree), elsegit diff --name-only "$(git merge-base HEAD "$(git rev-parse --abbrev-ref '@{upstream}' 2>/dev/null || echo origin/main)")"..HEAD, or the range the caller names. -
You are IN SCOPE if any changed path is under
src/ui/orsrc/styles/, is a presentation file undersrc/render/(a painter, a*_view.tscore, nameplates, VFX, the render budget), or issrc/game/ui_tier_knobs.ts/src/game/ui_effects_profile.ts. -
EARLY EXIT: if nothing matched, output exactly this and STOP:
Frontend seam review - out of scope. No
src/ui//src/styles// render presentation / tier-knob file in this change. Nothing to review. -
Otherwise read
src/ui/CLAUDE.md,src/styles/CLAUDE.md, andsrc/ui/hud/CLAUDE.md, then apply the checks below to the changed files only.
The prime directive (module-first)
A new window, panel, frame, or bar is its OWN module pair behind the pure-core + painter seam,
composed by Hud; NEVER a new banner section or method cluster on src/ui/hud.ts (the repo's
largest monolith) or src/render/renderer.ts. The deciding question: does the new code need
the coordinator's private mutable state (the Hud DOM and per-frame buffers, the renderer's
scene graph)? If no, it is a sibling module, every time. Flag any block of new presentation
logic grown onto a coordinator as a finding.
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.
- 13d ago First seen · 184 lines · 153 tokens per session scan A 5d47e00af164
frontend-seam-reviewer is an agent published in the GitHub repository levy-street/world-of-claudecraft (2,251 stars, last pushed yesterday), licensed MIT. It adds 153 tokens to every session and 3,300 once invoked, about $0.0008 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 2026-08-30.
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