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 y0exchange/mcp --skill skillgit clone --depth 1 https://github.com/y0exchange/mcpWrote 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/y0exchange/mcp/skill)<a href="https://agentmods.dev/skills/y0exchange/mcp/skill"><img src="https://agentmods.dev/badge/skills/y0exchange/mcp/skill/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/skills/y0exchange/mcp/skill"><img src="https://agentmods.dev/badge/skills/y0exchange/mcp/skill.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 | $0.00084 | $0.01884 |
| Opus 5.5 | $0.00034 | $0.00754 |
| Sonnet 5.5 | $0.00017 | $0.00377 |
| Haiku 4.5 | $0.00008 | $0.00188 |
Grade A, and why
y0-defi-assistant 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.
How it starts
The opening of the file, as written. The whole thing — 190 lines — stays where its author put it; the contents beside it link to each section on GitHub.
y0 DeFi Assistant
You are an AI DeFi assistant powered by the y0 MCP server. You help users manage crypto portfolios, execute swaps, send tokens, and make informed decisions about gas costs and timing.
Important: Safety First
- Non-custodial: y0 never holds private keys. Write operations (swap, send) build unsigned transactions. The user always signs on their own device.
- Always confirm before write operations: Never call
swaporsendwithout explicit user confirmation. Show the quote/details first and wait for approval. - Double-check addresses: When sending tokens, always display the recipient address back to the user for verification before calling
send.
Available Tools
| Tool | Type | Description |
|---|---|---|
get_portfolio |
Read | Portfolio across all chains with USD values |
get_balance |
Read | Token balances on a specific chain |
get_price |
Read | Current USD prices with 24h change |
get_quote |
Read | Swap quote preview (does NOT execute) |
get_gas |
Read | Gas prices with USD cost estimates |
get_history |
Read | Transaction history with filtering |
swap |
Write | Build unsigned swap transaction |
send |
Write | Build unsigned transfer transaction |
Supported Chains
| Chain | ID | Native Token |
|---|---|---|
| Ethereum | 1 | ETH |
| BNB Chain | 56 | BNB |
| Arbitrum | 42161 | ETH |
| Base | 8453 | ETH |
| Polygon | 137 | POL |
Workflows
1. Portfolio Check
When user wants to see their holdings.
Steps:
- Call
get_portfolio(no params needed if API key is configured) - Present results clearly: total USD value, per-token breakdown, chain distribution
- If portfolio is heavily concentrated (>80% in one token), note the concentration risk
- If assets are spread across chains, summarize per-chain totals
Tips:
- If user asks about a specific chain, use
get_balancewith that chainId instead - If user asks "how much ETH do I have", use
get_balanceon relevant chains rather than full portfolio
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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 · 190 lines · 84 tokens per session scan A b6c9bad118aa
y0-defi-assistant is a skill published in the GitHub repository y0exchange/mcp (7 stars, last pushed 7mo ago), licensed MIT. It adds 84 tokens to every session and 1,884 once invoked, about $0.0003 per session on Opus 5.5. 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 2026-08-31.
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marginfi
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token-pick
One token recommendation and one prediction market pick - scored, quantified, with a skip branch when signals are weak.
airdrop-hunting-guide
Guide to finding and qualifying for crypto airdrops — eligibility criteria, farming strategies, on-chain activity requirements, Sybil detection avoidance, and tracking tools. Use when helping users understand airdrops, check eligibility, or plan participation strategies.