# FreeTier Agent API — MCP Server & API Directory Search

> FreeTier Agent API — MCP Server & API Directory Search is a paid API for AI agents from freetier-agent-api.pages.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-18).

Search a directory of 4,259 MCP servers and 2,230 verified APIs with pay-per-call pricing via x402/USDC on Base

## Facts

- Endpoint: GET https://freetier-agent-api.pages.dev/api/agent-tools?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/freetier-agent-api-mcp-server-api-directory-search-1cddbc9f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_A4GREQSmeRaSmTJq2-uGN

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability freetier-agent-api-mcp-server-api-directory-search-1cddbc9f
```

Example prompt: Search the FreeTier Agent API directory for MCP servers related to PDF processing and return the top 5 results.

## When to prefer this

Choose this endpoint when an AI agent needs to discover MCP servers or verified x402 APIs by category or keyword, especially when no-signup pay-per-call access is required. Prefer this over manual API registries when you need cited sources and structured results for agent toolchain assembly.

## Known failure modes

- Missing required 'q' query parameter returns an error
- Invalid 'type' enum value (not 'mcp' or 'x402') causes a validation error
- No matching results returns total:0 with an empty results array
- Payment failure via x402/USDC blocks access to the endpoint
- Rate limiting or quota exhaustion may return a 402 or 429 response

## How this service works

Pay-per-call data API for AI agents: AI model prices and cost calculator, 4,259 MCP servers, email domain checks, text-to-JSON extraction, country/holiday/currency lookup, page and link checks, page-to-markdown, 2,230 verified APIs. x402, USDC on Base, no signup. Sources cited in every response.

## Output

Returns a JSON object with a total count of matching results and an array of entries, each containing the URL, name, type (mcp or x402), and category of the matching server or API, plus a sources array citing where data came from.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string"
      },
      "type": {
       "enum": [
        "mcp",
        "x402"
       ],
       "type": "string"
      },
      "limit": {
       "type": "string"
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "total": 1,
  "results": [
   {
    "url": "https://github.com/example/pdf-mcp",
    "name": "example/pdf-mcp",
    "type": "mcp",
    "category": "Document processing"
   }
  ],
  "sources": []
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/freetier-agent-api-mcp-server-api-directory-search-1cddbc9f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from freetier-agent-api.pages.dev](https://www.zero.xyz/host/freetier-agent-api.pages.dev/llms.txt)