blockchain-application

blockchain-application is a skill for Claude Code, Codex from j4flmao/agent-skills. It costs 175 tokens per session (5,532 once invoked), scanned A, original, MIT.

A guide to building blockchain applications such as smart contracts and decentralized apps across networks including Ethereum, Solana, Cardano, and Starknet.

In plain words
What is it for?
Use it to plan or implement tokens, DeFi, NFTs, governance, oracles, contract upgrades, and communication between smart contracts.
Why use it?
It helps choose suitable contract languages, designs, security measures, and deployment approaches for a target blockchain.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to plan or implement tokens, DeFi, NFTs, governance, oracles, contract upgrades, and communication between smart contracts.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/j4flmao/agent-skills/blockchain-application
Install

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.

Any agent
npx skills add j4flmao/agent-skills --skill blockchain-application
Clone the repo
git clone --depth 1 https://github.com/j4flmao/agent-skills

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for blockchain-application

README.md
[![agentmods](https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-application.svg)](https://agentmods.dev/skills/j4flmao/agent-skills/blockchain-application)
Your own site
<a href="https://agentmods.dev/skills/j4flmao/agent-skills/blockchain-application"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-application.svg" alt="Measured on agentmods" height="20"></a>
Per session 175 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,532 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00175 $0.05532
Opus 5 $0.00088 $0.02766
Sonnet 5 $0.00035 $0.01106
Haiku 4.5 $0.00017 $0.00553

Measured 4d ago against content hash 5712d79945a1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

blockchain-application 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 4d 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.

skills/blockchain/blockchain-application/SKILL.md · 542 lines

How it starts

The opening of the file, as written. The whole thing — 542 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Blockchain Application

Purpose

Guide smart contract development across all major blockchain platforms. Covers language selection, contract architecture, security patterns, gas optimization, deployment, and cross-contract communication. Platform-agnostic at the protocol layer; chain-specific at the language and VM layer.

Agent Protocol

Trigger

"smart contract", "solidity", "vyper", "evm", "rust smart contract", "solana contract", "anchor framework", "cardano", "plutus", "haskell contract", "cairo", "starknet", "sierra", "hardhat", "foundry", "truffle", "dapp backend", "contract deployment", "gas optimization", "contract security", "cross-contract call", "chainlink", "oracle contract", "defi contract", "nft contract", "move language", "sui contract", "aptos contract"

Input Context

  • Target blockchain and VM type (EVM/SVM/eUTxO/StarkNet/MoveVM)
  • Contract purpose (token/DeFi/NFT/oracle/governance/bridge)
  • Upgradeability requirements (proxy/non-upgradeable/beacon)
  • Security requirements (audit level, formal verification need)
  • Performance constraints (gas budget, compute units, TPS needs)
  • Existing dependencies (OpenZeppelin, Anchor libraries, Plutus contracts)

Output Artifact

Complete contract architecture specification: platform selection, contract design, implementation approach, testing strategy, deployment plan, security analysis.

Response Format

  1. Platform selection: chain type + VM + language + framework + toolchain
  2. Contract architecture: entry points, storage layout, external dependencies, upgradeability
  3. Implementation: key functions with gas considerations and security annotations
  4. Testing strategy: unit, integration, fuzz, invariant, testnet deployment
  5. Deployment: constructor args, verification, proxy setup, multi-sig ownership
  6. Risk analysis: known vulnerabilities specific to this platform/pattern

Completion Criteria

  • Contract architecture follows platform best practices (checks-effects-interactions, access control)
  • Storage layout compatible with upgradeability pattern (if upgradeable)
  • Gas optimization applied: storage reads minimized, calldata over memory where possible
  • Security review covers platform-specific attack vectors (reentrancy, oracle manipulation, flash loans)
  • Deployment plan includes verification, multi-sig ownership, and monitoring

Read the full file on GitHub · 542 lines

Changes

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.

  1. 4d ago First seen · 542 lines · 175 tokens per session scan A 5712d79945a1

Subscribe to this mod's changes

blockchain-application is a skill published in the GitHub repository j4flmao/agent-skills (21 stars, last pushed 2d ago), licensed MIT. It adds 175 tokens to every session and 5,532 once invoked, about $0.0009 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 2026-09-03.

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