MEV and sandwich attack probability scoring for DeFi transactions, paid per call via x402 on Base.
What it does
The `/api/mev/risk` endpoint is part of DeFi Shield, a suite of 69 paid API endpoints providing security intelligence for autonomous AI agents. This specific endpoint assesses MEV (Maximal Extractable Value) and sandwich attack probability for DeFi transactions. It accepts POST requests and costs $0.25 per call, settled in USDC on Base via the x402 protocol.
DeFi Shield covers 11 categories including DeFi intelligence, wallet profiling, protocol risk, NFT analysis, cross-chain comparisons, and real-time monitoring. The MEV & Trading category includes seven endpoints for risk assessment, optimal DEX routing, liquidity depth analysis, gas oracles, mempool scanning, price impact estimation, and arbitrage detection. Each endpoint supports free GET-based discovery (returning usage prompts and schema info) and paid POST requests requiring an x402 payment header.
The platform advertises agent-to-agent discovery via `/.well-known/agent-card.json`, a health endpoint at `/api/health` listing all endpoints and pricing, and analytics at `/api/analytics`. Payment settles only on successful response. No OpenAPI schema or detailed request/response documentation was found during crawling — the docs page returns 404 — so the exact input parameters and response format for `/api/mev/risk` must be inferred from context (likely a token address or transaction hash).
Capabilities
Use cases
- —Assess MEV exposure before submitting a DeFi swap transaction
- —AI agents autonomously evaluating sandwich attack probability for trade routing decisions
- —Portfolio management bots checking MEV risk as part of pre-trade analysis
- —DeFi dashboards displaying real-time MEV threat levels for pending trades
- —Automated trading systems incorporating MEV risk into execution strategy
Fit
Best for
- —AI agents needing on-demand MEV risk intelligence with micropayments
- —DeFi trading bots evaluating transaction safety before execution
- —Autonomous agents operating on Base that can pay in USDC via x402
Not for
- —Users needing free or subscription-based MEV protection (this is pay-per-call only)
- —Real-time MEV protection/blocking at the transaction level (this provides risk scoring, not active protection)
- —Non-crypto applications with no DeFi context
Quick start
# Free discovery (GET returns schema and usage prompt)
curl https://defi-shield-hazel.vercel.app/api/mev/risk
# Paid request (requires x402 payment header)
curl -X POST https://defi-shield-hazel.vercel.app/api/mev/risk \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{"address": "0x..."}'Example
Request
{
"address": "0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984"
}Endpoint
Quality
The endpoint is live (returns 402 on POST as expected for x402), and the landing page provides clear pricing ($0.25/call) and category context. However, no OpenAPI schema, no detailed docs (docs page is 404), no response examples, and the x402 challenge body was empty — so request/response formats are inferred. The example request is a best guess based on the quick-start pattern shown on the homepage.
Warnings
- —No OpenAPI or detailed API documentation available (docs page returns 404)
- —x402 challenge body was empty — no payment parameters (amount, token, network) were captured in the probe
- —Request and response schemas are inferred from homepage examples, not confirmed
- —Example request JSON is a guess based on similar endpoints listed on the site
Citations
- —The /api/mev/risk endpoint provides MEV and sandwich attack probability and costs $0.25 per callhttps://defi-shield-hazel.vercel.app
- —DeFi Shield has 69 paid API endpoints across 11 categories, priced $0.01–$2.50 per call, paid in USDC via x402 on Basehttps://defi-shield-hazel.vercel.app
- —Free endpoint discovery is available via GET on each endpoint, and agent discovery via /.well-known/agent-card.jsonhttps://defi-shield-hazel.vercel.app
- —Payment settles only on successful responsehttps://defi-shield-hazel.vercel.app