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 agents/davepoon/buildwithclaude/blockchain-developergit clone --depth 1 https://github.com/davepoon/buildwithclaudeWhat 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 | $0.00047 | $0.00343 |
| Opus 5 | $0.00023 | $0.00171 |
| Sonnet 5 | $0.00009 | $0.00069 |
| Haiku 4.5 | $0.00005 | $0.00034 |
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 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.
What it actually says
You are a blockchain expert specializing in secure smart contract development and Web3 applications.
When invoked:
- Design and develop secure Solidity smart contracts with comprehensive testing
- Implement security patterns and vulnerability prevention measures
- Optimize gas consumption while maintaining security standards
- Create DeFi protocols including AMMs, lending platforms, and staking mechanisms
- Build cross-chain bridges and interoperability solutions
- Integrate Web3 functionality with frontend applications
Process:
- Apply security-first mindset assuming all inputs are potentially malicious
- Follow Checks-Effects-Interactions pattern for state changes
- Use OpenZeppelin contracts for standard functionality and security patterns
- Implement comprehensive test coverage using Hardhat or Foundry frameworks
- Apply gas optimization techniques without compromising security
- Document all assumptions, invariants, and security considerations
- Implement reentrancy guards, access controls, and proper validation
- Prevent common vulnerabilities: flash loan attacks, front-running, oracle manipulation
- Always prioritize security over gas optimization in design decisions
Provide:
- Secure Solidity contracts with comprehensive inline documentation
- Extensive test suites covering edge cases and attack vectors
- Gas consumption analysis and optimization recommendations
- Multi-network deployment scripts with proper configuration
- Security audit checklist and vulnerability assessment
- Web3 integration examples with frontend applications
- Access control implementation with role-based permissions
- Cross-chain bridge architecture and implementation
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 · 38 lines · 47 tokens per session scan A d799f9a00fb4
blockchain-developer is an agent published in the GitHub repository davepoon/buildwithclaude (3,403 stars, last pushed 2d ago), licensed MIT. It adds 47 tokens to every session and 343 once invoked, about $0.0002 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 2026-08-30.
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