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Foundry: x402 Preflight and Base Contract Facts
x402
Foundry: x402 Preflight and Base Contract Facts is a paid API for AI agents from minty-sprout.onrender.com, paid per call via x402, $0.03/call, status unknown (last checked 2026-11-01).
Checks x402 payment endpoints before paying them and reads Base blockchain contracts for proxy, owner, and privileged role information directly from the chain.
Price / call$0.03
Success—
StatusUnknown
How this service works
Pay-per-call data for agents: check x402 sellers before paying them, and read Base contracts' proxy, owner and privileged powers straight from the chain.
Output
Returns structured data about an x402 seller (metadata, legitimacy signals) and/or a Base contract's proxy configuration, owner address, and privileged role assignments read directly from on-chain state.
Example use cases
Vet an x402 seller before paying
“I'm about to pay an x402 API at https://some-provider.onrender.com/v1/data — can you check if it looks legitimate and safe before I send USDC?”
Inspect Base contract ownership
“Who owns the Base smart contract at 0x1234567890abcdef1234567890abcdef12345678, and does it use a proxy pattern or have any special admin roles?”
Agent payment safety guard
“Before my workflow pays any x402 endpoint, run a preflight on https://api.thirdparty.com/premium-endpoint to confirm the seller details and flag anything suspicious.”
Technical details
Endpoint
POSThttps://minty-sprout.onrender.com/v1/schema-extract-guarded?utm_source=zero.xyzWhen to prefer
Use this endpoint when an AI agent needs to vet an x402 payment endpoint before committing USDC, or when it needs to read ownership and proxy structure of a Base network smart contract without setting up a direct RPC connection. Prefer this over generic blockchain explorers when you need structured, agent-ready output for x402 ecosystem due diligence specifically.
Side effects
- Invalid or unreachable x402 URL returns an error or empty seller info
- Contract address not found on Base returns null or not-deployed error
- Malformed input string causes a 400-level validation error
- Non-Base contract address (wrong chain) may return no results
- Rate limiting or upstream RPC failures may cause timeouts
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| input | string |
Tags
x402
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