x402 agent toolkit: service finder, payment safety, Solana & web tools

by dev.workers.moneytools.x402-pay-precheck

Ask your human to approve a payment

approval_request

Create a human approval request before paying (or any risky action). Returns approveUrl to show your human, agentToken and statusUrl. Needs X-API-Key on the MCP connection (monthly plan includes 20/day; credits: 3); without a key use HTTP POST https://approve.moneytools.dev/v1/approvals with x402 ($0.003). [served by approve.moneytools.dev]

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": {
      "title": "<title>"
    },
    "name": "approval_request"
  }
}

Input Schema

Name	Required	Description
`host`	No	Seller hostname or URL
`payTo`	No	0x recipient the agent will pay
`title`	Yes	What the agent wants to do, e.g. 'Pay api.example.com 0.50 USDC for a report'
`notify`	No	{ webhook?: https URL (signed POST), email?: address (limited availability), telegramChatId?: string (not enabled yet) }
`details`	No	Extra context for the human (max 1000 chars)
`network`	No	e.g. eip155:8453
`amountUsd`	No	Amount in USD the human approves (upper bound)
`ttlMinutes`	No	5-1440, default 30

Schema Changelog

Changes observed during successful MCP inspections.

First observedNov 4, 2026

TDQS

A4.1/5.0

Behavior5/5

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

Beyond the annotations (readOnly=false, destructive=false, openWorld=true, idempotent=false), the description discloses the return fields (approveUrl, agentToken, statusUrl), the auth requirement (X-API-Key on the MCP connection), concrete quota limits (20/day, 3 credits) and pricing for the fallback ($0.003). That is exactly the operational context annotations cannot carry.

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 purpose, then returns, then auth/quota, then fallback — a sensible priority order with no filler sentences. Minor waste in restating the host both in the URL and in the bracketed '[served by approve.moneytools.dev]' tag.

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 an 8-parameter, nested-object mutation tool with no output schema, the description still names the return payload, the auth and quota constraints, and a keyless alternative path. An agent has everything needed to call it correctly and to know what to display to its human.

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 the schema already explains host, payTo, title, notify, details, network, amountUsd and ttlMinutes. The description adds no syntax or format detail beyond implying the payment context; baseline 3 is appropriate.

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

Purpose4/5

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

The description leads with a specific verb+resource ('Create a human approval request') and scopes it to 'before paying (or any risky action)'. That implicitly separates it from the read/verify siblings (approval_status, approval_verify, approval_consume, approval_cancel), but no sibling is named explicitly, so differentiation requires the agent to infer from the verb.

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?

It gives a clear trigger condition — call this before paying or any risky action — which is exactly the when-to-use guidance an agent needs. It also covers the no-API-key path (HTTP POST with x402), but it doesn't name the downstream siblings an agent should call afterwards (approval_status/approval_consume), leaving the workflow chain implied.

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

All x402 agent toolkit: service finder, payment safety, Solana & web tools 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?