---
title: "Head Tool"
method: HEAD
path: "/tools/{tool_name}/call"
---

# Head Tool

`HEAD /tools/{tool_name}/call`

## Request

- Base URL: `https://agentpay.tools` (the document declares no server; this is the origin it was published from)
- URL: `https://agentpay.tools/tools/{tool_name}/call`
- Auth: none required

HEAD pre-flight for x402 discovery — answers 402, mirroring the GET probe.

Probers scoring "does the resource return 402?" treat any other status as
a failure, so HEAD returns the same 402 challenge as GET
/tools/{name}/call (status + PAYMENT-REQUIRED header incl.
extensions.bazaar, no pending row) with an empty body per HEAD semantics.
The X-Price-USDC/X-Pay-To pre-flight headers are kept for cost-check
callers.

## Path parameters

- `tool_name` string, required

## Response `200`

Successful Response

- unknown

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/agentpay/apis/agentpay-gateway.md) · [All operations](https://skmtc.dev/agentpay/apis/agentpay-gateway/llms.txt) · [OpenAPI document](https://skmtc.dev/agentpay/apis/agentpay-gateway/revisions/d4dd864c820e?raw)