# Metera

> The trust layer for AI agent data. Metera picks the source, verifies the answer, and labels how much to trust it.
> Any API can charge agents in USDC via x402.
> Any agent can pay for APIs autonomously.

## Overview

- [Marketplace](https://metera.xyz/marketplace): Browse all available APIs. Each entry includes name, price per call in USDC, and category.
- [Docs](https://metera.xyz/docs): Overview of the chat API, credits system, and marketplace.
- [MCP Integration](https://metera.xyz/docs/mcp-integration): Connect Claude Code, Cursor, Windsurf, Cline, or Codex to Metera via MCP.
- [Transparency](https://metera.xyz/transparency): Spending limits enforced on-chain via Squads Protocol v4 on Solana.

## For AI Agents

- [Connect](https://metera.xyz/developer/connect): Get your API key and MCP config for your editor.
- [API Keys](https://metera.xyz/api-keys): Create and manage API keys (mk_live_...).
- [Marketplace JSON](https://api.metera.xyz/api/marketplace): Machine-readable list of all available APIs with pricing.
- [MCP Registry JSON](https://api.metera.xyz/api/mcps): Machine-readable list of all paid MCP servers.
- [AGENTS.md](https://metera.xyz/AGENTS.md): Full agent-readable specification of Metera's capabilities, technical metadata, and integration instructions.
- npm package: @metera/mcp-client — programmatic access to any MCP server on the marketplace, with automatic x402 payment.

## For API Providers

- [List your API](https://metera.xyz/add-api): Register any API URL, set a price per call in USDC, go live in under 60 seconds.
- [Proxy Endpoints](https://api.metera.xyz/api/marketplace): All registered APIs accessible via https://api.metera.xyz/p/{slug}

## API Reference

- Chat: POST https://api.metera.xyz/api/chat (header: x-api-key)
- Balance: GET https://api.metera.xyz/api/chat/balance
- Marketplace: GET https://api.metera.xyz/api/marketplace
- MCP Registry: GET https://api.metera.xyz/api/mcps
- Agent Proxy (advanced x402): POST https://api.metera.xyz/agent/{agentKey}/fetch