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 nirholas/three.ws --skill cross-chain-bridge-guidegit clone --depth 1 https://github.com/nirholas/three.wsWrote 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/nirholas/three.ws/cross-chain-bridge-guide)<a href="https://agentmods.dev/skills/nirholas/three.ws/cross-chain-bridge-guide"><img src="https://agentmods.dev/badge/skills/nirholas/three.ws/cross-chain-bridge-guide.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00057 | $0.02135 |
| Opus 5 | $0.00028 | $0.01068 |
| Sonnet 5 | $0.00011 | $0.00427 |
| Haiku 4.5 | $0.00006 | $0.00214 |
Grade A, and why
cross-chain-bridge-guide 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.
How it starts
The opening of the file, as written. The whole thing — 211 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Cross-Chain Bridge Guide
Bridges move assets between blockchains. This guide covers how they work, which to use, and how to stay safe.
Why Bridges Exist
Each blockchain is an isolated system. Bridges connect them:
Ethereum ←──Bridge──→ Arbitrum
↕ ↕
Bridge Bridge
↕ ↕
Base ←──Bridge──→ Polygon
Use cases:
- Move ETH from Ethereum to Arbitrum for cheaper DeFi
- Access protocols only available on specific chains
- Consolidate assets scattered across chains
Bridge Architectures
Type 1: Native Bridges (Official L2 Bridges)
Used by rollup L2s to move between L1 and L2.
| Bridge | Route | Deposit Time | Withdrawal Time |
|---|---|---|---|
| Arbitrum Bridge | ETH ↔ Arbitrum | ~10 min | 7 days (fraud proof) |
| Optimism Bridge | ETH ↔ Optimism | ~10 min | 7 days (fraud proof) |
| Base Bridge | ETH ↔ Base | ~10 min | 7 days |
| zkSync Bridge | ETH ↔ zkSync | ~10 min | ~1 hour (ZK proof) |
The 7-day problem: Optimistic rollups require a 7-day challenge period for withdrawals to L1. This is why third-party bridges exist.
Type 2: Liquidity Network Bridges
Pre-fund liquidity on both chains. Users swap locally:
User deposits ETH on Chain A → Receives ETH from liquidity pool on Chain B
(No actual cross-chain message needed — just liquidity matching)
| Bridge | Speed | Chains | Best For |
|---|---|---|---|
| Stargate | 1–5 min | 15+ | Stablecoins, large amounts |
| Across | 2–10 min | 10+ | ETH, fast transfers |
| Hop | 5–20 min | 5+ | ETH, stablecoins |
Pros: Fast, no 7-day wait Cons: Limited by available liquidity, fees
Type 3: Message-Passing Bridges
Send a message cross-chain, mint/release on destination:
| Bridge | Mechanism | Chains |
|---|---|---|
| Wormhole | Guardian network validates | 30+ |
| LayerZero | Oracle + relayer (ultralight) | 30+ |
| Axelar | PoS validator network | 50+ |
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.
- 4d ago First seen · 211 lines · 57 tokens per session scan A 8ce38e4795e6
cross-chain-bridge-guide is a skill published in the GitHub repository nirholas/three.ws (111 stars, last pushed yesterday), licensed Apache-2.0. It adds 57 tokens to every session and 2,135 once invoked, about $0.0003 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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