# HydraTrader Research Brief

> HydraTrader Research Brief is a paid API for AI agents from x402.hydratrader.ai, paid per call via x402, $0.08/call, status unknown (last checked 2026-09-15).

Generates a cited research brief with key points, summary, confidence score, and caveats by searching the public web for a given question.

## Facts

- Endpoint: POST https://x402.hydratrader.ai/v1/research-brief
- Price: $0.08/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/hydratrader-research-brief-d95eeede
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fM2G_wtndvmFNIkoE_QZW

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 hydratrader-research-brief-d95eeede -d '<json body>'
```

Example prompt: Can you give me a standard research brief on how zero-knowledge proofs are being used in blockchain privacy — pull from up to 6 sources published in the last 90 days and flag any caveats?

## When to prefer this

Choose this endpoint when you need a structured, cited research brief with a confidence score and explicit caveats rather than raw search results or a full document dump. It is ideal for AI agents that need to answer factual questions with verifiable sources in a compact, structured format. Prefer it over generic search APIs when you want synthesis, not just links, and when you need to scope research to specific domains or recency windows. The cost floor of $0.08 USDC per call makes it appropriate for moderate-frequency research tasks where quality and citations matter more than raw speed.

## Known failure modes

- Question too short (under 12 characters) returns validation error
- Question exceeds 500 character limit returns 400
- No public sources found for the query returns low-confidence brief or error
- Denied domains conflict with available sources reduces result quality
- Payment failure via x402 returns 402 with payment terms
- Rate limiting or upstream search provider outage returns 5xx

## How this service works

Research brief with citations, key points, and caveats from the public web. When to use: short cited answers for agent questions (fair-use snippets only — no full-text dumps). USDC on Base via x402 (cost-floored) — no API key.

## Output

Returns a JSON object containing a headline, a prose summary, a list of key points, caveats, a confidence score (0-1), and an array of citations (each with URL, title, snippet, and publisher). Also includes usage metadata: sources used, latency in ms, estimated token cost in USDC, and the price paid.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "depth": {
   "enum": [
    "quick",
    "standard"
   ],
   "type": "string",
   "default": "standard"
  },
  "scope": {
   "type": "object",
   "properties": {
    "max_sources": {
     "type": "integer",
     "default": 5,
     "maximum": 8,
     "minimum": 1
    },
    "domains_deny": {
     "type": "array",
     "items": {
      "type": "string"
     }
    },
    "recency_days": {
     "type": "integer"
    },
    "domains_allow": {
     "type": "array",
     "items": {
      "type": "string"
     }
    }
   }
  },
  "question": {
   "type": "string",
   "maxLength": 500,
   "minLength": 12
  },
  "client_ref": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "brief": {
   "caveats": [
    "Ecosystem evolving quickly; always check live facilitator docs"
   ],
   "summary": "x402 is an open payment protocol that uses HTTP 402 Payment Required so clients (including AI agents) can pay for web resources with stablecoins, commonly USDC on Base, via a facilitator that verifies and settles.",
   "headline": "x402 turns HTTP 402 into USDC micropayments for agents",
   "confidence": 0.78,
   "key_points": [
    "Server returns 402 with payment terms; client pays and retries",
    "CDP Facilitator commonly used for verify/settle on Base",
    "Bazaar indexes discoverable paid routes"
   ]
  },
  "usage": {
   "floor_mult": 1.3,
   "latency_ms": 6400,
   "price_usdc": "0.08",
   "sources_used": 3,
   "token_cost_est_usdc": "0.05"
  },
  "endpoint": "research-brief",
  "citations": [
   {
    "url": "https://docs.cdp.coinbase.com/x402/buyer/discover-services",
    "title": "x402 Bazaar (Discovery Layer)",
    "snippet": "The x402 Bazaar is a catalog of payment-gated services discovered by the CDP Facilitator.",
    "published": null,
    "publisher": "Coinbase CDP"
   }
  ],
  "client_ref": null
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/hydratrader-research-brief-d95eeede/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.hydratrader.ai](https://www.zero.xyz/host/x402.hydratrader.ai/llms.txt)