Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/0xlayerghost/solidity-agent-kit/claude-code-usagenpx skills add 0xlayerghost/solidity-agent-kit --skill claude-code-usagegit clone --depth 1 https://github.com/0xlayerghost/solidity-agent-kitWhat 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 | $0.00055 | $0.02222 |
| Opus 5 | $0.00028 | $0.01111 |
| Sonnet 5 | $0.00011 | $0.00444 |
| Haiku 4.5 | $0.00006 | $0.00222 |
Grade A, and why
claude-code-usage 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 2d 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.
This is a copy
100% identical to claude-code-usage — 1 line differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 223 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Claude Code Best Practices
Language Rule
- Always respond in the same language the user is using. If the user asks in Chinese, respond in Chinese. If in English, respond in English.
Context Management Rules
| Rule | Why |
|---|---|
| One window = one task | Mixing tasks pollutes context and degrades output quality |
Use /clear over /compact |
Clean start is more reliable than compressed context |
/clear after complex tasks |
Prevents old context from interfering with new work |
| Copy key info to new windows | Don't rely on context persistence — paste critical details |
Task Execution Strategy
| Task Type | Recommended Approach |
|---|---|
| Small bug fix (few lines) | Describe directly, let Claude modify in-place |
| Large feature / refactor | /plan → review approach → /clear → paste plan → execute step by step |
| Multi-file changes | Must use /plan workflow — never modify multiple files without a plan |
| Code analysis / learning | Ask Claude to analyze directly — no plan needed |
| Debugging | Provide error message + file path + relevant code — ask for root cause |
Prompt Techniques
Do This
- Give specific paths: "Modify the
_transferfunction insrc/MyToken.sol" - Give examples: "Input: 100 tokens, Expected: 95 tokens after 5% fee"
- Set boundaries: "Only modify this function, don't touch other code"
- Reference tests: "The fix should make
test_transfer_feeDeductionpass"
Avoid This
- Vague references: "Modify that transfer function" — which one? Where?
- Open-ended requests without constraints: "Make it better"
- Multiple unrelated tasks in one message
Ambiguity Resolution — When Instructions Are Unclear
When a user instruction is vague, open-ended, or could be interpreted in multiple ways, do NOT guess and proceed. Proactively analyze the instruction and present all possible interpretations for the user to confirm before taking action.
Trigger Conditions
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.
- 2d ago First seen · 223 lines · 55 tokens per session scan A 9774e6f85091
claude-code-usage is a skill published in the GitHub repository 0xlayerghost/solidity-agent-kit (4 stars, last pushed 22d ago), licensed MIT. It adds 55 tokens to every session and 2,222 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to claude-code-usage, differing in 1 line, and is treated as a copy.
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