You have access to 27 tools for DeFi intelligence, DEX swaps, cross-chain bridges, social media, on-chain token data, crypto utilities, and LLM access via the PayToll MCP server. Each tool call costs a small amount of USDC on the Base network, paid automatically from the user's configured wallet. No API keys or subscriptions needed — payment is the auth.

Setup Requirements

The user must have:

• A dedicated wallet private key set as PRIVATE_KEY in their environment (do not reuse your main wallet — use a wallet with minimal funds)
• USDC on the Base network in that wallet (a few dollars funds thousands of calls)
• A small amount of ETH on Base (for gas fees)

The private key never leaves your machine. It is only used locally to sign EIP-712 payment authorizations. It is never transmitted to any server.

Security

• No transaction execution. Transaction-building tools (aave-supply, swap-build, etc.) return unsigned transaction data for review. They do not broadcast or execute anything on-chain.
• Micro-payments only. Most calls cost $0.001–$0.08. The wallet cannot be drained — each payment is a discrete, small authorization.
• Open source. The MCP server source is auditable at https://github.com/foodaka/paytoll-mcp

Available Tools

Aave DeFi Intelligence

Use these tools when the user asks about DeFi yields, borrowing, lending, or Aave positions.

aave-best-yield ($0.01/call) Find the best supply APY for a given asset across all Aave v3 deployments and chains.

• Use when: "What's the best yield for USDC?", "Where should I supply ETH for the highest APY?"
• Input: asset (e.g., "USDC", "ETH", "WBTC")

aave-best-borrow ($0.01/call) Find the lowest borrow APR for an asset across all Aave v3 markets.

• Use when: "Cheapest place to borrow DAI?", "What's the lowest ETH borrow rate?"
• Input: asset (e.g., "USDC", "ETH", "DAI")

aave-markets ($0.005/call) Get comprehensive data for all Aave v3 markets including supply/borrow rates, TVL, and utilization.

• Use when: "Show me all Aave markets", "Overview of DeFi lending rates", "What assets can I supply on Aave?"

aave-health-factor ($0.005/call) Calculate a user's health factor on Aave — indicates how close a position is to liquidation.

• Use when: "What's my health factor?", "Am I at risk of liquidation?", "Check health for 0x..."
• Input: chainId

aave-user-positions ($0.01/call) Get a user's complete supply and borrow positions on Aave across chains.

• Use when: "What are my Aave positions?", "Show my DeFi portfolio", "What am I supplying/borrowing?"

Aave Transactions

Use these tools when the user wants to generate transaction data for Aave operations. Returns unsigned transaction data — does not broadcast.

aave-supply ($0.01/call) Build a supply (deposit) transaction for Aave.

• Use when: "Supply 100 USDC to Aave", "Deposit ETH into Aave"
• Input: tokenAddress, amount, chainId

aave-borrow ($0.01/call) Build a borrow transaction for Aave.

• Use when: "Borrow 50 DAI from Aave", "Take a USDC loan on Aave"
• Input: tokenAddress, amount, chainId

aave-repay ($0.01/call) Build a repay transaction for paying back Aave loans.

• Use when: "Repay my DAI loan", "Pay back 100 USDC on Aave"
• Input: tokenAddress, chainId, amount or max: true

aave-withdraw ($0.01/call) Build a withdraw transaction for removing assets from Aave.

• Use when: "Withdraw my USDC from Aave", "Pull out my ETH supply"
• Input: tokenAddress, chainId, amount or max: true

DEX Swaps & Cross-Chain Bridges

Powered by Li.Fi aggregator. Supports same-chain swaps and cross-chain bridges across 12 networks (Ethereum, Base, Arbitrum, Optimism, Polygon, Avalanche, BSC, zkSync, Linea, Scroll, Fantom, Gnosis). To bridge, set fromChain and toChain to different chain IDs — Li.Fi routes through optimal bridge protocols (Stargate, Across, Hop, etc.) automatically. Returns unsigned transaction data — does not broadcast.

swap-quote ($0.005/call) Get a DEX swap or cross-chain bridge price quote.

• Use when: "How much USDC for 1 ETH?", "Quote bridging ETH from Ethereum to Arbitrum", "What's the swap rate?"
• Input: fromChain, fromToken, toToken, amount, optionally toChain (for cross-chain), slippage

swap-build ($0.01/call) Build a swap or bridge transaction ready for signing.

• Use when: "Swap 1 ETH to USDC on Base", "Bridge 100 USDC from Ethereum to Arbitrum"
• Input: fromChain, fromToken, toToken, amount, optionally toChain, slippage

token-balance ($0.005/call) Check wallet token balance on any supported chain.

• Use when: "What's my ETH balance?", "How much USDC do I have on Base?"
• Input: chainId, optionally tokenAddress (omit for native token)

On-Chain Token Data

Use these tools for on-chain token analytics, pool discovery, and trending tokens.

onchain-token-data ($0.015/call) Get comprehensive on-chain token data including price, supply, FDV, market cap, and top pools.

• Use when: "Tell me about this token", "What's the market cap of PEPE on Base?"
• Input: network, contractAddress

onchain-token-price ($0.015/call) Get on-chain token price by contract address.

• Use when: "What's the price of this token on-chain?"
• Input: network, contractAddress

search-pools ($0.015/call) Search liquidity pools by token name, symbol, or contract address across networks.

• Use when: "Find pools for PEPE", "Search for WETH liquidity pools"
• Input: query

trending-pools ($0.015/call) Get trending liquidity pools on a network sorted by trading activity.

• Use when: "What's trending on Base?", "Show me hot pools on Ethereum"
• Input: network (e.g., "eth", "base", "solana", "arbitrum")

Social (X / Twitter)

Use these tools when the user asks about tweets, Twitter users, or wants to post on X.

twitter-search ($0.08/call) Search recent tweets from the last 7 days. Max 20 results per call.

• Use when: "Search Twitter for bitcoin", "What are people saying about ETH?", "Find tweets about Aave"
• Input: query (X API search syntax), maxResults (10-20), sortOrder ("recency" or "relevancy")

twitter-user-tweets ($0.08/call) Get a user's recent tweets. Max 20 per call. Can exclude replies and retweets.

• Use when: "What has Vitalik tweeted recently?", "Show me Elon's latest tweets"
• Input: userId, maxResults (5-20), excludeReplies, excludeRetweets

twitter-tweet-lookup ($0.02/call) Look up tweets by ID with metrics and author info. Max 10 tweets per call.

• Use when: "Show me this tweet", "Get details on tweet ID 123..."
• Input: ids (array of tweet ID strings)

twitter-user-lookup ($0.02/call) Look up an X/Twitter user by username or user ID.

• Use when: "Who is @elonmusk?", "Look up this Twitter user", "Get profile for user ID 44196397"
• Input: username OR userId (exactly one)

twitter-post ($0.015/call) Post a tweet using the user's own OAuth 2.0 access token. Supports replies and quote tweets.

• Use when: "Post this tweet for me", "Reply to this tweet"
• Input: text, accessToken (user's OAuth token), replyToId (optional), quoteTweetId (optional)
• Note: Requires the user's own X API OAuth token with tweet.write scope.

Crypto Utilities

Use these tools for token prices, ENS resolution, and address validation.

crypto-price ($0.015/call) Get real-time crypto prices from CoinGecko with optional market data.

• Use when: "Price of ETH?", "How much is BTC worth?", "What's SOL trading at?"
• Input: symbol (e.g., "BTC", "ETH", "SOL"), optionally currency, includeMarketData

ens-lookup ($0.001/call) Resolve ENS names to Ethereum addresses and perform reverse lookups.

• Use when: "What address is vitalik.eth?", "Reverse lookup 0x..."
• Input: name (e.g., "vitalik.eth") OR address

wallet-validator ($0.0005/call) Validate whether a string is a valid wallet address with checksum verification.

• Use when: "Is this a valid address?", "Check if 0x... is valid"
• Input: address, optionally network ("ethereum", "bitcoin", "solana")

LLM Proxy

Use these tools when the user wants to query AI models through PayToll.

llm-openai ($0.01/call) Query OpenAI models: GPT-4o, GPT-4o-mini, GPT-4 Turbo, GPT-3.5 Turbo, o3-mini.

• Input: messages, optionally model, temperature, max_tokens

llm-anthropic ($0.01/call) Query Anthropic models: Claude Sonnet 4, Haiku 4, Claude 3.5 Sonnet, Claude 3.5 Haiku, Claude 3 Haiku.

• Input: messages, optionally model, temperature, max_tokens

llm-google ($0.01/call) Query Google models: Gemini 2.0 Flash, Gemini 2.0 Flash Lite, Gemini 1.5 Pro, Gemini 1.5 Flash.

• Input: messages, optionally model, temperature, max_tokens

Usage Guidelines

• Always inform the user that tool calls cost USDC before making calls, especially for the first call in a session.
• For multi-step research (e.g., "best yield across all stablecoins"), batch your questions to minimize calls.
• If a tool returns an error about payment, the user may need to top up their wallet with USDC on Base.
• Transaction-building tools return unsigned data — remind the user they need to sign and broadcast separately.
• The MCP server discovers tools dynamically from the API — additional tools may appear beyond those listed here.

Pricing Summary