# Book402 Summary Search

> Book402 Summary Search is a paid API for AI agents from book402.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Full-text search within book summaries and transcriptions to find specific concepts, ideas, or passages across a curated book library

## Facts

- Endpoint: GET https://book402.com/search/summaries
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/book402-summary-search-31d28541
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zjBluCIz1FYKFWLbGL6rf

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 book402-summary-search-31d28541
```

Example prompt: Search Book402's summary database for passages about compound interest and show me the top 5 most relevant excerpts.

## When to prefer this

Use this endpoint when you need to retrieve specific concept-level knowledge or passages from within book summaries — ideal when you want to know what a curated book library says about a topic, validate an idea against book content, or find relevant excerpts without reading full books. Prefer over general web search when book-sourced, curated knowledge is specifically needed.

## Known failure modes

- Missing required query parameter 'q' returns a 400 error
- Empty or overly broad query may return low-relevance excerpts
- Query with no matches returns an empty results array
- Rate limiting or payment failure returns a 402 status requiring USDC payment
- Server errors return 500 with no results

## How this service works

Full-text search within book summaries and transcriptions for specific concepts or passages. Query param: q (string, required), limit (number, optional, default 20). Example: GET /search/summaries?q=compound+interest. Returns JSON with matching excerpts.

## Output

A JSON array of matching results, each containing a book ID, title, and a relevant text excerpt from the book's summary or transcription that matches the query.

## 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"
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "results": [
   {
    "id": 42,
    "title": "Atomic Habits",
    "excerpt": "...compound interest of self-improvement..."
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/book402-summary-search-31d28541/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from book402.com](https://www.zero.xyz/host/book402.com/llms.txt)