boo-x402-mcp

by lucle87

Overview Schema Source Related Servers Discussions Admin

JavaScript

Local

Check x402 spend in this session

x402_spend_status

Check current USDC spend for the session and view configured per-call and total spend caps.

Instructions

FREE. Shows how much USDC has been spent this session and the configured spend caps (per call and total).

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "x402_spend_status"
  }
}

Input Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jul 11, 2026

TDQS

A3.5/5.0

Behavior3/5

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

No annotations provided, so description must cover behavioral traits. It states the operation is read-only (shows spend) and free, but does not disclose any session scope requirements, rate limits, or whether data is persistent across calls.

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

Conciseness5/5

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

One sentence, 15 words, no redundancy. Every word adds value: 'FREE' signals cost, 'shows' is the action, 'USDC spent' and 'spend caps' are the output.

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

Completeness4/5

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

For a parameterless tool with no output schema, the description adequately explains the return values (spent amount and caps). It covers the essential context for an agent to decide whether to call it.

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

Parameters4/5

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

The input schema has zero parameters, so baseline is 4. The description adds no parameter-specific info, which is acceptable since none exist.

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 clearly states it shows USDC spend and spend caps for the session. The title reinforces this, making the purpose unambiguous. However, it does not explicitly differentiate from sibling tools like x402_list_paid_tools, which could cause minor confusion.

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

Usage Guidelines2/5

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

No guidance on when to use this tool versus alternatives (e.g., x402_list_paid_tools for listing pay-per-call tools). The note 'FREE' hints at cost advantage but does not specify conditions or exclusions.

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