# Briefs402 Research Literature Brief

> Briefs402 Research Literature Brief is a paid API for AI agents from briefs402.worlddata402.workers.dev, paid per call via x402, $0.5/call, status unknown (last checked 2026-10-30).

Generates a ready-made literature review brief on any research topic by fusing arXiv and Crossref sources, written by Llama 3.3 70B under strict no-fabrication rules, paid via USDC on Base mainnet over x402.

## Facts

- Endpoint: GET https://briefs402.worlddata402.workers.dev/v1/brief/research?utm_source=zero.xyz
- Price: $0.5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/briefs402-research-literature-brief-e1b279cb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_G0XUlsC3_iEkHiMX30AHX

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 briefs402-research-literature-brief-e1b279cb
```

Example prompt: Can you pull together a literature review brief on federated learning — I want the key facts, paper counts, and a confidence rating, in English?

## When to prefer this

Choose this endpoint when you need a fast, multi-source academic literature brief on any topic without setting up API keys or accounts, especially when paying per-query via USDC on Base mainnet. It is ideal for agents that need trustworthy, no-fabrication research summaries fusing arXiv and Crossref data, and supports Arabic output for non-English use cases. Prefer over general web search when structured academic facts with confidence scoring matter.

## Known failure modes

- Query string too short (under 2 characters) or too long (over 200 characters) returns validation error
- Unsupported lang value (not 'en' or 'ar') causes request rejection
- arXiv or Crossref upstream unavailability may result in partial or empty key_facts
- Payment failure over x402 (insufficient USDC balance or wrong network) blocks access
- Very niche topics may return low confidence or minimal paper counts

## How this service works

Ready-made intelligence reports for AI agents: company, country, daily market, EU tenders, domain due diligence, location, literature review, food product, package risk and document translation briefs. Each brief fuses several live data sources and is written by Llama 3.3 70B under strict no-fabrication rules (English or Arabic). USDC on Base mainnet over x402. No API key, no account.

## Output

Returns a JSON object with the research subject, key facts including number of books, arXiv results count, Crossref results count, year range of publications, and an overall confidence rating (e.g. 'high'). The summary is written in English or Arabic as specified, synthesized by Llama 3.3 70B from live academic data sources under no-fabrication rules.

## 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",
       "maxLength": 200,
       "minLength": 2,
       "description": "Research topic"
      },
      "lang": {
       "enum": [
        "en",
        "ar"
       ],
       "type": "string",
       "default": "en",
       "description": "Output language of the summary: en (default) or ar (Arabic)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "subject": "Research: agent payments protocol",
  "key_facts": {
   "books": 5,
   "year_range": "2019–2026",
   "arxiv_results": 10,
   "crossref_results": 10
  },
  "confidence": "high"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/briefs402-research-literature-brief-e1b279cb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from briefs402.worlddata402.workers.dev](https://www.zero.xyz/host/briefs402.worlddata402.workers.dev/llms.txt)