Discovery Files

xpay✦ Tools provides machine-readable discovery files so AI agents and search engines can find and understand available tools.

Overview

Every xpay MCP endpoint publishes standard discovery files:

File	URL	Purpose
`llms.txt`	`https://{slug}.mcp.xpay.sh/llms.txt`	LLM-friendly tool catalog
`skill.md`	`https://{slug}.mcp.xpay.sh/skill.md`	Skill definition for AI agents
`.well-known/mcp.json`	`https://{slug}.mcp.xpay.sh/.well-known/mcp.json`	MCP server metadata

These files are also available on the platform domain:

File	URL
`llms.txt`	`https://xpay.tools/llms.txt`
`agents.txt`	`https://xpay.tools/agents.txt`
`skill.md`	`https://xpay.tools/skill.md`
`openapi.json`	`https://xpay.tools/openapi.json`
`.well-known/mcp.json`	`https://xpay.tools/.well-known/mcp.json`

llms.txt

A text file designed for LLMs to quickly understand what tools are available. It lists each tool with its name, description, and pricing.


# Firecrawl MCP Server
> Web scraping and crawling tools

- firecrawl_scrape: Scrape a single URL ($0.01)
- firecrawl_crawl: Crawl a website ($0.05)
- firecrawl_search: Search the web ($0.01)

skill.md

A Markdown file that describes the MCP server’s capabilities in a format that AI agents can use to decide whether to connect.

.well-known/mcp.json

A JSON file following the emerging .well-known/mcp.json standard for MCP server discovery:


{
  "name": "xpay✦ Tools",
  "description": "1000+ pay-per-use AI tools",
  "url": "https://mcp.xpay.sh/mcp",
  "transport": "streamable-http",
  "authentication": {
    "type": "query",
    "parameter": "key"
  }
}

How Agents Use Discovery Files

AI agents (like Claude, ChatGPT, or custom agents) can:

Fetch llms.txt to get a quick overview of available tools
Read skill.md to understand the server’s capabilities
Parse .well-known/mcp.json to get the connection URL and auth method
Connect to the MCP endpoint and start using tools

This enables fully autonomous tool discovery — agents can find and connect to xpay✦ Tools without human configuration.