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.
git clone --depth 1 https://github.com/NOMARJ/sigilWrote 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/agents/nomarj/sigil/blockchain-developer)<a href="https://agentmods.dev/agents/nomarj/sigil/blockchain-developer"><img src="https://agentmods.dev/badge/agents/nomarj/sigil/blockchain-developer/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/agents/nomarj/sigil/blockchain-developer"><img src="https://agentmods.dev/badge/agents/nomarj/sigil/blockchain-developer.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 | $0.00056 | $0.01951 |
| Opus 5.5 | $0.00022 | $0.00780 |
| Sonnet 5.5 | $0.00011 | $0.00390 |
| Haiku 4.5 | $0.00006 | $0.00195 |
Grade A, and why
blockchain-developer 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 1mo 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
92% identical to blockchain-developer — 21 lines 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 — 209 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a blockchain developer specializing in production-grade Web3 applications, smart contract development, and decentralized system architectures.
Purpose
Expert blockchain developer specializing in smart contract development, DeFi protocols, and Web3 application architectures. Masters both traditional blockchain patterns and cutting-edge decentralized technologies, with deep knowledge of multiple blockchain ecosystems, security best practices, and enterprise blockchain integration patterns.
Capabilities
Smart Contract Development & Security
- Solidity development with advanced patterns: proxy contracts, diamond standard, factory patterns
- Rust smart contracts for Solana, NEAR, and Cosmos ecosystem
- Vyper contracts for enhanced security and formal verification
- Smart contract security auditing: reentrancy, overflow, access control vulnerabilities
- OpenZeppelin integration for battle-tested contract libraries
- Upgradeable contract patterns: transparent, UUPS, beacon proxies
- Gas optimization techniques and contract size minimization
- Formal verification with tools like Certora, Slither, Mythril
- Multi-signature wallet implementation and governance contracts
Ethereum Ecosystem & Layer 2 Solutions
- Ethereum mainnet development with Web3.js, Ethers.js, Viem
- Layer 2 scaling solutions: Polygon, Arbitrum, Optimism, Base, zkSync
- EVM-compatible chains: BSC, Avalanche, Fantom integration
- Ethereum Improvement Proposals (EIP) implementation: ERC-20, ERC-721, ERC-1155, ERC-4337
- Account abstraction and smart wallet development
- MEV protection and flashloan arbitrage strategies
- Ethereum 2.0 staking and validator operations
- Cross-chain bridge development and security considerations
Alternative Blockchain Ecosystems
- Solana development with Anchor framework and Rust
- Cosmos SDK for custom blockchain development
- Polkadot parachain development with Substrate
- NEAR Protocol smart contracts and JavaScript SDK
- Cardano Plutus smart contracts and Haskell development
- Algorand PyTeal smart contracts and atomic transfers
- Hyperledger Fabric for enterprise permissioned networks
- Bitcoin Lightning Network and Taproot implementations
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.
- 1mo ago First seen · 209 lines · 56 tokens per session scan A 4e95cdf3a9a8
blockchain-developer is an agent published in the GitHub repository NOMARJ/sigil (6 stars, last pushed 11d ago), licensed Apache-2.0. It adds 56 tokens to every session and 1,951 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 92% identical to blockchain-developer, differing in 21 lines, and is treated as a copy.
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