MCP Server: Onchain Yield Tools for Claude, Cursor, and Any MCP Client

The Vaults.fyi MCP server connects MCP-compatible clients to the full Vaults.fyi data and transaction surface. Discovery, history, recommendations, position tracking, and transaction building are all callable as tools — your client decides which to use and how to chain them. Hosted at https://mcp.vaults.fyi/mcp over streamable HTTP. 38 tools. Bearer-token auth. No server-side private keys: every transaction tool returns calldata for your client to sign.

What people use it for

A few prompts that exercise meaningful tool chains:

Discover yield

“Find me the best USDC yields right now with TVL over $10M and no active warnings.”

“What yields beat the USDC benchmark by more than 200 bps over the last 30 days?”

Filter by curator or protocol

“Show me Steakhouse and Gauntlet curated Morpho vaults across all stablecoins.”

“Which Aave v3 markets have the highest USDC supply APY across networks?”

Model layered yield

“I’d consider sUSDe and sUSDS — find vaults with composite APY above 8% accounting for the underlying asset rate.”

Run history and benchmarks

“Plot Fluid USD Vault APY against the USDC benchmark for the last 90 days.”

Audit positions

“Audit positions for 0xabc… — total deposited, current value, unclaimed rewards, and any flagged exposure.”

Build transaction payloads

“Build a deposit of 10,000 USDC into the highest-rated Morpho vault on Base and return the calldata.”

Quickstart

You’ll need a Vaults.fyi API key. Request one at portal.vaults.fyi.

Recommended setup

Configure Vaults.fyi across supported MCP clients with one command:

npx @vaultsfyi/scripts init-mcp --api-key YOUR_VAULTS_API_KEY

To configure one client:

npx @vaultsfyi/scripts init-mcp --api-key YOUR_VAULTS_API_KEY --client cursor

The installer creates or updates your local MCP config and adds the vaults-fyi server entry without removing existing servers. Supported clients: Claude Desktop, Cursor, Claude Code, Windsurf, VS Code, Zed, Amazon Q, and GitHub Copilot CLI. Restart your client after installation. The 38 Vaults.fyi tools should appear in the client’s MCP tools list.

Without --api-key, the installer prompts interactively. In CI and other non-interactive environments, pass --api-key.

Manual setup

Claude Desktop
Claude Code
Cursor & other clients

Claude Desktop may require a local bridge for remote MCP servers. Add Vaults.fyi through mcp-remote in your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS, %APPDATA%\Claude\claude_desktop_config.json on Windows):

claude_desktop_config.json

{
  "mcpServers": {
    "vaults-fyi": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote@latest",
        "https://mcp.vaults.fyi/mcp",
        "--header",
        "Authorization:${VAULTS_AUTH_HEADER}",
        "--transport",
        "http-only"
      ],
      "env": {
        "VAULTS_AUTH_HEADER": "Bearer YOUR_VAULTS_API_KEY"
      }
    }
  }
}

Restart Claude Desktop. The 38 Vaults.fyi tools will appear in the tools menu.

Add the server with one command:

claude mcp add --transport http vaults-fyi https://mcp.vaults.fyi/mcp \
  --header "Authorization: Bearer YOUR_VAULTS_API_KEY"

Verify with claude mcp list.

Any client that supports streamable-HTTP MCP works. Point it at https://mcp.vaults.fyi/mcp and pass Authorization: Bearer YOUR_VAULTS_API_KEY as a header.Health check:

curl -i https://mcp.vaults.fyi/health

What you can do

Six capability surfaces, each backed by several tools:

Discover and filter

Search across networks, protocols, assets, curators, and tags. Filter by TVL, APY, score, and active warnings in a single structured query.

Evaluate risk

Reputation Scores and inline flags (bad debt exposure, qualified-investor gates, depegs, recent incidents) ship with the data. No separate lookup.

Analyze history

APY, TVL, share-price, and total-return time series for any vault. Asset-price history and benchmark APY for relative performance.

Build transaction payloads

Deposit, withdraw, claim rewards, and approve. Tools return decoded calldata and signing instructions; your client signs and submits.

Track portfolios

Aggregate positions and rewards across networks for any address. Drill into per-position cost basis and event history.

Operate on tokens

Approve, transfer, wrap, and unwrap as primitives — useful when an agent is composing multi-step flows.

Tool inventory

38 tools, grouped by purpose. Each returns structured JSON optimized for agent consumption.

Discovery and search (7)

Tool	Purpose
`vaults_search`	Filtered search across vaults (TVL, APY, score, curator, tags, warnings)
`vaults_list`	Paginated full vault list
`networks`	Supported chains
`protocols`	Supported protocols
`assets`	Supported assets
`curators`	Named curators (79+)
`tags`	Vault tags (e.g., `top-curator`, `lst`, `rwa`)

Vault detail (3)

Tool	Purpose
`vault_details`	Full vault metadata, including flags and Reputation Score
`vault_apy`	Current APY (headline, base, rewards, composite)
`vault_tvl`	Current TVL

History and benchmarks (8)

Tool	Purpose
`vault_apy_history`	APY time series
`vault_tvl_history`	TVL time series
`vault_share_price_history`	Share-price time series
`vault_history`	Combined APY/TVL/share-price
`vault_returns`	Realized total returns
`asset_price_history`	Underlying asset price
`benchmark_apy`	Asset-level benchmark APY
`benchmark_apy_history`	Benchmark APY time series

Recommendations (2)

Tool	Purpose
`best_vault`	Single best-fit vault for a given asset/criteria
`best_deposit_options`	Ranked deposit options

Wallet and positions (6)

Tool	Purpose
`positions`	All positions for an address
`position_details`	Per-position cost basis, current value, P&L
`wallet_balances`	Token balances across networks
`token_balance`	Single token balance
`user_events`	Deposit/withdraw/claim history
`rewards`	Outstanding reward entitlements

Vault transactions (7)

Tool	Purpose
`transaction_context`	Pre-flight context (allowance, balances, gas)
`build_vault_tx`	Deposit/withdraw calldata with decoded steps
`build_claim_rewards`	Claim calldata for a single vault
`claim_all_rewards`	Multi-vault claim calldata
`withdraw_all_positions`	Multi-vault withdraw calldata
`submit_tx_hash`	Register a submitted hash for status tracking
`get_transaction_status`	Status of a tracked transaction

Token utilities (5)

Tool	Purpose
`approve_erc20`	ERC-20 approval calldata
`transfer_erc20`	ERC-20 transfer calldata
`transfer_native`	Native transfer calldata
`wrap_native`	Wrap native to wrapped equivalent
`unwrap_native`	Unwrap

Authentication

Every request requires a bearer token:

Authorization: Bearer YOUR_VAULTS_API_KEY

The API key is forwarded only to Vaults.fyi API calls and is never placed in signing URLs or transaction payloads.

Request a key at portal.vaults.fyi. For keyless pay-per-request access via USDC on Base, see x402.

Signing model

Transaction tools (build_vault_tx, build_claim_rewards, approve_erc20, etc.) return structured calldata, not signed transactions. The server holds no private keys. Each response includes:

stepDecodings — human-readable description of each call
signingInstructions — step-by-step guidance for the signer
signingPaths — supported signing surfaces (e.g., wallet, OWS)
submitTool — the tool to call after signing (submit_tx_hash)
statusTool — the tool to call for status (get_transaction_status)

This keeps key custody with the client. Agents that integrate with OpenWallet Standard can sign and submit without leaving the conversation.

Going further

AI agents overview

The full surface area for agents: MCP, x402, and the LLM-optimized API reference.

Keyless access via x402

Pay-per-request access on Base, no API key required.

LLM-optimized API reference

Full reference at llms.txt and llms-full.txt.

OpenAPI spec

Underlying REST API the MCP wraps.

Start Here

Core Concepts

Methodology

SDK

AI & Agents

Plans & Billing

Resources

MCP Server: Onchain Yield Tools for Claude, Cursor, and Any MCP Client

What people use it for

Quickstart

Recommended setup

Manual setup

What you can do

Discover and filter

Evaluate risk

Analyze history

Build transaction payloads

Track portfolios

Operate on tokens

Tool inventory

Authentication

Signing model

Going further

AI agents overview

Keyless access via x402

LLM-optimized API reference

OpenAPI spec

​What people use it for

​Quickstart

​Recommended setup

​Manual setup

​What you can do

Discover and filter

Evaluate risk

Analyze history

Build transaction payloads

Track portfolios

Operate on tokens

​Tool inventory

​Authentication

​Signing model

​Going further

AI agents overview

Keyless access via x402

LLM-optimized API reference

OpenAPI spec

What people use it for

Quickstart

Recommended setup

Manual setup

What you can do

Tool inventory

Authentication

Signing model

Going further