ScorpTech x402 API

X402 Probe

x402_probe

Read-onlyIdempotent

x402 preflight for AI agents: inspect any paid endpoint BEFORE paying. Fetches the unpaid 402, decodes PAYMENT-REQUIRED (v2 header or v1 body), normalises price to USD, lists networks/assets/payTo/feePayer, validates the offer and Bazaar discovery schema, checks PayAI and Coinbase CDP discovery listing, and returns an OK/RISKY/BROKEN verdict. Never pays the target. Price: $0.005 USDC per successful call (x402, Solana). Same tool over HTTPS: GET https://scorptech.it.com/api/x402/v1/x402-probe

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "url": "<url>"
    },
    "name": "x402_probe"
  }
}

Input Schema

Name	Required	Description
`url`	Yes	x402 endpoint URL
`body`	No	optional JSON body for POST probes (default {})
`method`	No	HTTP method (default GET)

Schema Changelog

Changes observed during successful MCP inspections.

First observedOct 23, 2026

TDQS

A4.4/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Goes well beyond the readOnly/idempotent/non-destructive annotations by disclosing cost ($0.005 USDC per successful call), the fact that the target is never paid, the header/body decoding variants, and the exact verdict semantics. This is rich behavioral context an agent needs before invoking.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core purpose and preflight guarantee, then supporting detail. Slightly long with the alternate HTTPS endpoint and pricing, but every clause conveys actionable information rather than padding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 3-param tool with no output schema, the description covers what is returned (normalised price, networks/assets/payTo/feePayer, verdict) and what is validated, so an agent knows both inputs and output shape.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so url, body, and method are already documented. The description adds only an implicit hint that the default flow is a GET probe to fetch the 402, but does not enrich parameter meaning beyond the schema. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: fetches the unpaid 402, decodes PAYMENT-REQUIRED, normalises price, validates the offer, returns an OK/RISKY/BROKEN verdict. This is clearly differentiable from sibling http_probe and headers_audit because it is purpose-built for x402 payment inspection.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly tells the agent to run it BEFORE paying and that it never pays the target, which is the key usage condition. It does not name a sibling alternative or exclusions, but the 'preflight' framing gives clear context for when to call it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

All ScorpTech x402 API tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?