Borrowing it
Nothing to install: this file belongs to joshsymonds/savecraft.gg. 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/joshsymonds/savecraft.gg/main/.claude/skills/working-on-d2r/SKILL.mdgit clone --depth 1 https://github.com/joshsymonds/savecraft.ggWrote 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/joshsymonds/savecraft.gg/working-on-d2r)<a href="https://agentmods.dev/skills/joshsymonds/savecraft.gg/working-on-d2r"><img src="https://agentmods.dev/badge/skills/joshsymonds/savecraft.gg/working-on-d2r/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/skills/joshsymonds/savecraft.gg/working-on-d2r"><img src="https://agentmods.dev/badge/skills/joshsymonds/savecraft.gg/working-on-d2r.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 | $0.00080 | $0.00909 |
| Opus 5 | $0.00040 | $0.00454 |
| Sonnet 5 | $0.00016 | $0.00182 |
| Haiku 4.5 | $0.00008 | $0.00091 |
Grade A, and why
working-on-d2r 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 10d 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 — 76 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Working on the D2R Parser
The parser lives in plugins/d2r/d2s/. It's a WASM plugin that reads .d2s binary save files and emits ndjson to stdout. See docs/plugins.md for the plugin contract and working-on-plugins skill for section design guidance.
Verification
cd plugins/d2r && just test # D2R-specific tests
just test-go # Full Go test suite
just lint-go # Includes D2R with relaxed lint rules
D2R v105 (Reign of the Warlock) Specifics
This parser targets v105 only (version byte 0x69). Classic LoD saves are not supported.
Expansion detection: v105+ saves do NOT set the LoD status bit (0x20) in the header. You must check header.Realm >= RealmLoD to gate mercenary and golem parsing. This is a common trap — the LoD bit check works for older saves but silently misparses v105.
Warlock class: Class index 7. Skill offset is 373 (not 281 — those are monster skills). Skills.txt extracted via CASC.
Item codes: Huffman-encoded in D2R (not ASCII like LoD). The Huffman tree is in d2s/huffman.go.
ISC (ItemStatCost): RotW ISC is IDENTICAL to vanilla D2R — zero property bit width changes. RotW added properties 365 (sB=6) and 366 (sB=8), plus items not in vanilla tables.
Lint Exceptions
golangci-lint config has exclusions for plugins/d2r/:
- govet/shadow (binary parsing has lots of shadowed
err) - globals (lookup tables are package-level)
- complexity (binary parsing functions are inherently complex)
- magic numbers (byte offsets, bit widths)
These exclusions are intentional. Don't try to "fix" them.
Test Data
- Primary test save:
reference/Diablo II Resurrected/Atmus.d2s— Level 74 Warlock, 45 items + 3 merc items. - Reference implementation:
reference/olegbl-d2rmm/.../d2s/d2/items.ts—readItem()function.
CASC Data
Game data tables are extracted from the D2R CASC archive:
- Archive:
reference/d2r-casc/(gitignored, must copy locally) - Extracted tables:
reference/d2r-rotw-excel/(gitignored — Blizzard IP, NEVER check in) - Extract tool:
plugins/d2r/tools/casc-extract/(uses CascLib, cloned at build time) - Plugin
devenv.nixadds cmake/gcc/zlib for building the extract tool
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.
- 10d ago First seen · 76 lines · 80 tokens per session scan A 158c9e8ea996
working-on-d2r is a skill published in the GitHub repository joshsymonds/savecraft.gg (12 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 80 tokens to every session and 909 once invoked, about $0.0004 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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gameobject-component-destroy
Destroy one or more Components from a target GameObject. Missing (null) components are skipped — they cannot be destroyed. Use 'gameobject-find' and 'gameobject-component-get' to identify the components first.
unity-version-split
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unity-addressables
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unity-manual-component
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