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 paritytech/polkadot-apps --skill polkadot-utilitiesgit clone --depth 1 https://github.com/paritytech/polkadot-appsWrote 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/paritytech/polkadot-apps/polkadot-utilities)<a href="https://agentmods.dev/skills/paritytech/polkadot-apps/polkadot-utilities"><img src="https://agentmods.dev/badge/skills/paritytech/polkadot-apps/polkadot-utilities/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/paritytech/polkadot-apps/polkadot-utilities"><img src="https://agentmods.dev/badge/skills/paritytech/polkadot-apps/polkadot-utilities.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 | $0.00083 | $0.02355 |
| Opus 5.5 | $0.00033 | $0.00942 |
| Sonnet 5.5 | $0.00017 | $0.00471 |
| Haiku 4.5 | $0.00008 | $0.00235 |
Grade A, and why
polkadot-utilities 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 2mo 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 — 194 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Polkadot Utility Packages
Five leaf packages provide foundational utilities across the monorepo. All are pure TypeScript, framework-agnostic, and published under the @polkadot-apps/ scope.
Decision Guide
| Need | Package | Import |
|---|---|---|
| Encode/decode SS58 addresses, validate addresses, convert between SS58 and H160 EVM addresses | address |
@polkadot-apps/address |
| Symmetric encryption (AES-GCM, ChaCha20), key derivation (HKDF), asymmetric encryption (NaCl box), random bytes | crypto |
@polkadot-apps/crypto |
| Byte encoding/decoding (hex, UTF-8, concat), hashing (blake2b-256, sha2-256, keccak-256), token formatting (planck to human-readable and back) | utils |
@polkadot-apps/utils |
| Persistent key-value storage that auto-detects browser localStorage vs host container backend | storage |
@polkadot-apps/storage |
| Structured logging with levels, namespaces, and pluggable handlers | logger |
@polkadot-apps/logger |
Quick Start: Address
import {
isValidSs58,
ss58Decode,
ss58Encode,
normalizeSs58,
ss58ToH160,
h160ToSs58,
truncateAddress,
} from "@polkadot-apps/address";
// Validate
isValidSs58("5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY"); // true
// Decode to raw bytes + network prefix
const { publicKey, prefix } = ss58Decode("5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY");
// Re-encode with Polkadot prefix (0)
const polkadotAddr = normalizeSs58("5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY", 0);
// SS58 <-> H160 EVM address conversion
const evmAddr = ss58ToH160("5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY");
const ss58Addr = h160ToSs58("0x9621dde636de098b43efb0fa9b61facfe328f99d");
// Display
truncateAddress("5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY"); // "5Grwva...utQY"
Quick Start: Crypto
import {
xchachaEncrypt,
xchachaDecrypt,
deriveKey,
randomBytes,
sealedBoxEncrypt,
sealedBoxDecrypt,
} from "@polkadot-apps/crypto";
// Symmetric encryption (XChaCha20-Poly1305 recommended for random nonces)
const key = randomBytes(32);
const { ciphertext, nonce } = xchachaEncrypt(data, key);
const plaintext = xchachaDecrypt(ciphertext, key, nonce);
// Key derivation
const encKey = deriveKey(masterSecret, "myapp-v1", "encryption");
// Asymmetric sealed box (anonymous sender)
import nacl from "tweetnacl";
const recipient = nacl.box.keyPair();
const sealed = sealedBoxEncrypt(message, recipient.publicKey);
const opened = sealedBoxDecrypt(sealed, recipient.secretKey);
What ships with it
5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 2mo ago First seen · 194 lines · 83 tokens per session scan A 52c8566d1767
polkadot-utilities is a skill published in the GitHub repository paritytech/polkadot-apps (2 stars, last pushed 3d ago), licensed Apache-2.0. It adds 83 tokens to every session and 2,355 once invoked, about $0.0003 per session on Opus 5.5. 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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