# x402stock Free Seller API Quote & Purchase Guide

> x402stock Free Seller API Quote & Purchase Guide is a free API for AI agents from agents.x402stock.xyz, callable via x402, Free, status healthy (last checked 2026-10-12, last successful call 2026-10-07).

Returns a free, wallet-free quote with API contract details, pricing, prerequisites, and next steps for any x402stock data task — no purchase executed.

## Facts

- Endpoint: POST https://agents.x402stock.xyz/zeroclick/agent/quote?utm_source=zero.xyz
- Price: Free
- Payment: x402
- Status: healthy
- Last checked: 2026-10-12
- Last successful call: 2026-10-07
- Success rate: 67% of calls made through Zero
- Rating: 3.7 / 5 from 1 review
- Activations on Zero: 3
- Provider: agents.x402stock.xyz
- Website: https://agents.x402stock.xyz
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agents-x402stock-xyz-x402stock-free-seller-api-quote-purchase-guide-bdd18fd9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ucYa9m7ysTmzZPO0kUXd1

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 agents-x402stock-xyz-x402stock-free-seller-api-quote-purchase-guide-bdd18fd9 -d '<json body>'
```

Example prompt: I want to pull short interest history for US stocks using x402stock — can you get me a free quote and purchase guide so I know the exact API contract, price per call, and what I need to get started?

## When to prefer this

Use this endpoint when an agent needs to discover, plan, or price a data purchase on x402stock before committing any funds — especially when no wallet is available or when a human needs to review costs first. Prefer this over the paid endpoints when the task is exploratory, the right contract is uncertain, or when a budget needs to be validated. This is also ideal for autonomous agents that need to determine prerequisites and auth requirements before executing a purchase.

## Known failure modes

- status: needs_input — goal description too vague to match a contract; agent should refine the goal field
- status: unsupported — requested data type not available on x402stock
- status: unavailable — service temporarily unreachable
- status: blocked — request violates policy (e.g. credentials included in goal)
- status: unknown — ambiguous task, no confident match found

## How this service works

Market and economic data for AI agents — US stocks, ETFs and options, forex, crypto and on-chain perps, energy commodities (crude, natural gas, gasoline), US and global macro (Fed funds, CPI/PCE, jobs, GDP, Treasury debt & yields, World Bank indicators), SEC filings, congressional trades, and market sentiment. No API keys, no accounts. Pay per request in USDC via x402 or MPP. This server is a pay-per-use, transparent proxy in front of x402stock's own API: it handles identity, payment, and proxying. Agents can purchase autonomously or with their human's approval. The complete verified paid surface is listed at /openapi.json, the source of truth for available operations. Each operation here carries its live price in x-payment-info. Use the operations and details here when they meet your needs. Filtered specs contain only matching operations; if you cannot find what you need here, use search or the service catalog. The live catalog at /manifest.json is authoritative for prices and any free included units (prices[].includedUnits) - some meters include free usage per account before any charge, reserved for agents claimed by a human with a verified email.

## Output

Returns a JSON object with a status enum (quoted, ready, needs_input, blocked, unknown, unsupported, unavailable), a priceUsd field always equal to '0', a Markdown-formatted guide string containing the matched API contract, pricing, prerequisites, and next steps, and a guideUrl pointing to a wallet-free advisor endpoint for further planning.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "goal": {
   "type": "string",
   "maxLength": 2000,
   "minLength": 1,
   "description": "Describe the task and known inputs. Do not include credentials."
  },
  "payment": {
   "enum": [
    "x402",
    "mpp",
    "card"
   ],
   "type": "string",
   "description": "Known payment method for the eventual purchase, independent of this free lookup's wallet proof."
  },
  "quantity": {
   "type": "integer",
   "maximum": 1000000,
   "minimum": 1,
   "description": "Number of API calls, not returned items. Omit when unknown; describe desired output in goal."
  },
  "budgetUsd": {
   "type": "string",
   "pattern": "^(0|[1-9]\\d{0,8})(\\.\\d{1,6})?$",
   "description": "Total cash budget in USD. A quote does not authorize spending."
  },
  "requirements": {
   "type": "string",
   "maxLength": 300,
   "minLength": 1
  },
  "humanAvailable": {
   "type": "boolean",
   "description": "Whether a human is in the loop. False recommends anonymous auth for a new autonomous identity; omit when unknown. Executing a human's request without further interruptions does not by itself mean false."
  },
  "budgetExclusive": {
   "type": "boolean"
  },
  "reviewAfterCalls": {
   "type": "integer",
   "maximum": 1000000,
   "minimum": 1
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "guide": "Task support is not established. Use the advisor to resolve missing details before purchasing.",
  "status": "unknown",
  "guideUrl": "https://agents.x402stock.xyz/zeroclick/agent/guide",
  "priceUsd": "0"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agents-x402stock-xyz-x402stock-free-seller-api-quote-purchase-guide-bdd18fd9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agents.x402stock.xyz](https://www.zero.xyz/host/agents.x402stock.xyz/llms.txt)