blockchain-cross-chain

blockchain-cross-chain is a skill for Claude Code, Codex from j4flmao/agent-skills. It costs 108 tokens per session (5,445 once invoked), scanned A, original, MIT.

A guide to connecting different blockchains so they can transfer assets or exchange messages. It explains bridges, which move information or tokens between otherwise separate networks.

In plain words
What is it for?
Use it to design bridges, cross-chain messaging, asset transfers, atomic swaps, and interoperability systems.
Why use it?
It helps compare cross-chain protocols and understand their trust assumptions, security risks, fees, and performance.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: positional $N argument.

Good fit Use it to design bridges, cross-chain messaging, asset transfers, atomic swaps, and interoperability systems.

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

README.md
[![agentmods](https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-cross-chain/github.svg)](https://agentmods.dev/skills/j4flmao/agent-skills/blockchain-cross-chain)
Your own site
<a href="https://agentmods.dev/skills/j4flmao/agent-skills/blockchain-cross-chain"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-cross-chain/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.

agentmods 80×15 button for blockchain-cross-chain

Your own site · 80×15
<a href="https://agentmods.dev/skills/j4flmao/agent-skills/blockchain-cross-chain"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-cross-chain.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 108 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,445 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 warn 7 Sept 2026
SkillSpector: 1 finding, 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 Excessive Agency · line 129
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 $0.00108 $0.05445
Opus 5 $0.00054 $0.02722
Sonnet 5 $0.00022 $0.01089
Haiku 4.5 $0.00011 $0.00545

Measured 4d ago against content hash 45c000c78476, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

blockchain-cross-chain 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-cross-chain/SKILL.md · 513 lines

How it starts

The opening of the file, as written. The whole thing — 513 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Blockchain Cross-Chain

Purpose

Guide cross-chain protocol selection, bridge architecture, and interoperability design. Covers all major cross-chain protocols with their trust models, security implications, and integration patterns.

Agent Protocol

Trigger Keywords

"cross-chain", "bridge", "IBC", "LayerZero", "Wormhole", "Axelar", "CCIP", "interop", "atomic swap", "shared sequencer", "cross-chain message", "wrapped token", "canonical bridge", "light client bridge", "GMP", "interchain", "multichain"

Input Context

  • Problem type (asset transfer/message passing/data query/atomic execution)
  • Source and destination chains with finality models
  • Security requirements (trust minimization, audit level, value secured)
  • Performance needs (latency, throughput, cost budget)
  • Existing infrastructure (current bridge usage, token standards)

Output Artifact

Cross-chain architecture specification: protocol selection, trust model, fee model, security analysis, implementation plan.

Response Format

## Cross-Chain Analysis

**Protocol**: <IBC | LayerZero | Wormhole | Axelar | CCIP | ZK-Bridge | Custom>

**Source Chain**: <chain + finality model>
**Destination Chain**: <chain + finality model>

**Mechanism**:
- <transport layer: light client / oracle / guardian / DON / ZK proof>
- <message delivery: relayer / executor / keeper>
- <security: verification type + trust assumptions>

**Considerations**:
- <finality mismatch> | <token representation> | <fee model> | <failure handling>

**Recommendation**:
- <contract changes, relayer setup, timeout config, rate limit, pause mechanism>

Completion Criteria

  • Protocol selection justified against alternatives with trust model comparison
  • Finality divergence modeled with confirmation depth specification
  • Fee model covers relayer economics on both sides
  • Failure modes documented: timeouts, reorgs, rate limits, paused state
  • Security analysis identifies bridge-specific attack vectors

Max Response Length

4000 tokens

Read the full file on GitHub · 513 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 Changed 45c000c78476
  2. 8d ago First seen · 513 lines · 108 tokens per session scan A ceb654fcb58e

Subscribe to this mod's changes

blockchain-cross-chain is a skill published in the GitHub repository j4flmao/agent-skills (23 stars, last pushed 5d ago), licensed MIT. It adds 108 tokens to every session and 5,445 once invoked, about $0.0005 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.