DeFi Yield Finder API

Best DeFi yields ranked by APY -- lending, staking, LP across 100+ protocols. Powered by DeFiLlama. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.

Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.

Quickstart -- MCP

Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):

{
  "mcpServers": {
    "defi-yields": {
      "url": "https://defi-yields.api.klymax402.com/mcp"
    }
  }
}

Quickstart -- HTTP (x402)

curl "https://defi-yields.api.klymax402.com/api/yields?token=..."
# -> 402 Payment Required, with an x402 payment challenge in the response body

Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.

Tools

Tool	Method	Path	Price	Description
`defi_find_best_yields`	GET	`/api/yields`	$0.005	Find best DeFi yield opportunities for a token
`defi_find_best_yields`	POST	`/api/yields`	$0.005	Find best DeFi yield opportunities for a token (POST variant)

`defi_find_best_yields`

Use this when you need to find the best DeFi yields for a token across all chains and protocols. Returns ranked opportunities in JSON.

Parameters

Name	Type	Required	Description
`token`	string	yes	Token symbol to find yields for (e.g. USDC, ETH, WBTC)
`chain`	string	no	Filter by chain (e.g. base, ethereum, arbitrum, polygon). Optional — returns all chains if omitted.
`minTvl`	number	no	Minimum TVL in USD to filter pools (default: 100000)
`limit`	number	no	Number of results to return (default: 10, max: 50)

Returns

pool -- pool/vault name and pair
protocol -- protocol name (Aave, Compound, Lido, Aerodrome, etc.)
chain -- which blockchain network
apy -- current annual percentage yield
tvl -- total value locked in USD
riskLevel -- risk assessment (low/medium/high)
type -- yield type (lending, staking, LP, vault)

Example response:

{"pools":[{"pool":"USDC Lending","protocol":"Aave V3","chain":"base","apy":4.82,"tvl":125000000,"riskLevel":"low","type":"lending"}],"token":"USDC","totalPools":15}

When to use: deploying idle capital to find the highest safe yield. Essential for yield optimization and DeFi strategy comparison.

Not for: swap quotes (use dex_get_swap_quote), wallet balance (use wallet_get_portfolio), liquidation risk (use defi_get_liquidation_levels).

`defi_find_best_yields`

Use this when you need to find the best DeFi yields for a token across all chains and protocols. Returns ranked opportunities in JSON. POST variant of defi_find_best_yields -- same params passed as JSON body instead of query string.

Parameters

Name	Type	Required	Description
`token`	string	yes	Token symbol to find yields for (e.g. USDC, ETH, WBTC)
`chain`	string	no	Filter by chain (e.g. base, ethereum, arbitrum, polygon). Optional — returns all chains if omitted.
`minTvl`	number	no	Minimum TVL in USD to filter pools (default: 100000)
`limit`	number	no	Number of results to return (default: 10, max: 50)

Returns

pool -- pool/vault name and pair
protocol -- protocol name (Aave, Compound, Lido, Aerodrome, etc.)
chain -- which blockchain network
apy -- current annual percentage yield
tvl -- total value locked in USD
riskLevel -- risk assessment (low/medium/high)
type -- yield type (lending, staking, LP, vault)

Example response:

{"pools":[{"pool":"USDC Lending","protocol":"Aave V3","chain":"base","apy":4.82,"tvl":125000000,"riskLevel":"low","type":"lending"}],"token":"USDC","totalPools":15}

When to use: deploying idle capital to find the highest safe yield. Essential for yield optimization and DeFi strategy comparison.

Not for: swap quotes (use dex_get_swap_quote), wallet balance (use wallet_get_portfolio), liquidation risk (use defi_get_liquidation_levels).

Example agent prompts

"Find the best DeFi yields for a token across all chains and protocols"
"Find the best DeFi yields for a token across all chains and protocols"

Payment

Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
Network: Base L2 (eip155:8453)
Asset: USDC
Facilitator: Coinbase CDP (primary), PayAI (fallback)
Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)

Part of klymax402

100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.

Catalog: https://klymax402.com/llms.txt
Full API reference: https://klymax402.com/llms-full.txt
Live stats: https://klymax402.com/stats

License

MIT