# AgentIndex x402 Research

> AgentIndex x402 Research is a paid API for AI agents from x402.agentindex.world, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-30).

Answers a research question by searching the web, verifying claims, and synthesizing a cited, fact-checked answer with source attribution

## Facts

- Endpoint: GET https://x402.agentindex.world/research?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentindex-x402-research-4e7e36a4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HUbo9AIJBd7KmuPKTx_py

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 agentindex-x402-research-4e7e36a4
```

Example prompt: Research what caused the recent Base network congestion in September 2026, checking up to 8 web sources, and give me a fact-checked answer with citations.

## When to prefer this

Choose this endpoint when you need a synthesized, cited, fact-checked answer to a research question rather than a raw list of search results. It is especially valuable when source verification matters — e.g. fact-checking claims, investigating recent events, or producing reports that require attribution. Prefer it over a plain web-search endpoint when you want the synthesis and verification step done automatically and returned as a single structured response. Pay-per-call pricing at $0.005 USDC makes it cost-effective for on-demand agent queries without subscriptions.

## Known failure modes

- Query exceeds 500 characters — request rejected with validation error
- max_sources out of range (not 1-10) — validation error
- No relevant web sources found — answer may be empty or low-confidence
- Payment not settled via x402/USDC on Base — 402 Payment Required returned
- Transient web fetch failures may reduce source count below requested max
- Claims verification may be inconclusive if sources conflict — claims_verified_reason will explain

## How this service works

Jev-powered research: routed search, cited answer, claims verified against sources. Ask a question, get a 5-8 sentence answer, each claim tagged to a numbered source, built from real page content - no invented facts. A fast paid LLM writes it, under 4.5s guaranteed; on a rare miss, a no-LLM extractive fallback (top sentences from the sources, picked by Jev) takes over instead, marked "synthesis":"extractive". Try GET /research/sample.

## Output

A JSON object containing: a synthesized `answer` (plain text, with inline citation markers like [1][2]); a `sources` array with URL, title, source type, and published date for each reference; a `timing_ms` breakdown (total, search, verify, synthesis); and a `claims_verified` boolean with an optional `claims_verified_reason` explaining any caveats.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "query": {
   "type": "string",
   "description": "The research question to answer, up to 500 characters."
  },
  "max_sources": {
   "type": "integer",
   "description": "How many web sources to consider, 1-10. Default 5."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "query": "What caused the 2026 Base network congestion in September?",
  "answer": "Base experienced elevated congestion in mid-September 2026 driven by a surge in memecoin launch activity on Uniswap V2/V3 and Aerodrome [1]. Average gas prices briefly spiked above typical levels during peak trading windows [1][2]. The Base team noted no protocol-level incident and attributed the load to organic demand rather than an attack [2]. Several DEX aggregators reported temporarily degraded quote latency during the same window [3]. Network conditions normalized within about a day as launch volume subsided [1].",
  "sources": [
   {
    "url": "https://example.com/base-report",
    "title": "Base network activity report",
    "source": "web",
    "published_at": "2026-09-15T00:00:00Z"
   },
   {
    "url": "https://example.com/gas-tracker",
    "title": "Gas price tracker",
    "source": "web",
    "published_at": "2026-09-16T00:00:00Z"
   },
   {
    "url": "https://example.com/dex-status",
    "title": "DEX aggregator status page",
    "source": "web",
    "published_at": "2026-09-15T00:00:00Z"
   }
  ],
  "timing_ms": {
   "total": 3170,
   "search": 1450,
   "verify": 720,
   "synthesis": 980
  },
  "claims_verified": true,
  "claims_verified_reason": null
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentindex-x402-research-4e7e36a4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentindex.world](https://www.zero.xyz/host/x402.agentindex.world/llms.txt)