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 skills add besoeasy/open-skills --skill check-crypto-address-balancegit clone --depth 1 https://github.com/besoeasy/open-skillsWrote 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/besoeasy/open-skills/check-crypto-address-balance)<a href="https://agentmods.dev/skills/besoeasy/open-skills/check-crypto-address-balance"><img src="https://agentmods.dev/badge/skills/besoeasy/open-skills/check-crypto-address-balance/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/besoeasy/open-skills/check-crypto-address-balance"><img src="https://agentmods.dev/badge/skills/besoeasy/open-skills/check-crypto-address-balance.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 14 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Data Exfiltration · line 16 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 48 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 57 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 135 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 18 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 67 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 73 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 136 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 21 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 119 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 51 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 83 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 98 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 144 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
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 | $0.00020 | $0.02246 |
| Opus 5 | $0.00010 | $0.01123 |
| Sonnet 5 | $0.00004 | $0.00449 |
| Haiku 4.5 | $0.00002 | $0.00225 |
Grade B, and why
check-crypto-address-balance scanned grade B with 2 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 12d 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.
Sends data to an external URLmediumData exfiltration
A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.
const res = await fetch('https://api.mainnet-beta.solana.com', { method: 'POST', Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -s "https://blockchain.info/q/addressbalance/1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa" How it starts
The opening of the file, as written. The whole thing — 196 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Check Crypto Address Balance Skill
Query cryptocurrency address balances across multiple blockchains using free public APIs. Supports Bitcoin, Ethereum, BSC, Solana, Litecoin, and other major chains without requiring API keys for basic queries.
Supported chains & best free APIs
| Chain | API | Base URL | Rate limit | Notes |
|---|---|---|---|---|
| Bitcoin (BTC) | Blockchain.info | https://blockchain.info |
~1 req/10s | Most reliable, no key needed |
| Bitcoin (BTC) | Blockstream | https://blockstream.info/api |
Generous | Esplora API, open-source |
| Ethereum (ETH) | Etherscan | https://api.etherscan.io/api |
5 req/sec (free) | Optional key for higher limits |
| Ethereum (ETH) | Blockchair | https://api.blockchair.com |
30 req/min | Multi-chain support |
| BSC (BNB) | BscScan | https://api.bscscan.com/api |
5 req/sec (free) | Same API as Etherscan |
| Solana (SOL) | Public RPC | https://api.mainnet-beta.solana.com |
Varies by node | Free public nodes |
| Solana (SOL) | Solscan API | https://public-api.solscan.io |
10 req/sec | No key for basic queries |
| Litecoin (LTC) | BlockCypher | https://api.blockcypher.com/v1/ltc/main |
200 req/hr | Multi-chain API |
| Litecoin (LTC) | Chain.so | https://chain.so/api/v2 |
Generous | Simple JSON responses |
| Multi-chain | Blockchair | https://api.blockchair.com |
30 req/min | BTC, ETH, LTC, DOGE, BCH |
Skills
Bitcoin (BTC) balance
# Using Blockchain.info (satoshis, convert to BTC by dividing by 100000000)
curl -s "https://blockchain.info/q/addressbalance/1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa"
# Using Blockstream (satoshis)
curl -s "https://blockstream.info/api/address/1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa" | jq '.chain_stats.funded_txo_sum - .chain_stats.spent_txo_sum'
Node.js:
async function getBTCBalance(address) {
const res = await fetch(`https://blockchain.info/q/addressbalance/${address}`);
const satoshis = await res.text();
return parseFloat(satoshis) / 1e8; // convert satoshis to BTC
}
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.
- 12d ago First seen · 196 lines · 20 tokens per session scan B f6b9a37b5967
check-crypto-address-balance is a skill published in the GitHub repository besoeasy/open-skills (132 stars, last pushed 8d ago), licensed MIT. It adds 20 tokens to every session and 2,246 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it B with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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