# klymax402 Vector Search API

> klymax402 Vector Search API is a paid API for AI agents from klymax402.com, paid per call via x402, $0.012/call, status unknown (last checked 2026-09-15).

Performs semantic vector search over a provided or session-stored set of text documents, returning the top-K most relevant results for a given query.

## Facts

- Endpoint: GET https://klymax402.com/api/vector-search/api/search
- Price: $0.012/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/klymax402-vector-search-api-55c13cee
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_p2qYPgjhFjkDJEIwRWTiL

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 klymax402-vector-search-api-55c13cee
```

Example prompt: Search through these 5 product descriptions for the one most relevant to 'wireless noise-cancelling headphones for travel', and return the top 2 matches from the 'products' namespace.

## When to prefer this

Choose this endpoint when you need lightweight, pay-per-call semantic vector search without setting up a dedicated vector database or managing API keys. It is well-suited for session-scoped document retrieval tasks where you want to index a small-to-medium corpus on the fly and query it immediately. Prefer it over full-featured vector DBs (Pinecone, Weaviate) when you want zero infrastructure overhead and are already operating within the klymax402 x402 payment ecosystem.

## Known failure modes

- No documents provided and no session-stored documents found for the namespace — returns empty results or an error
- topK exceeds the maximum of 10 — capped or returns an error
- Query string is empty or missing — returns a validation error
- Payment not received or insufficient USDC balance — returns HTTP 402
- Namespace not found or misspelled — returns empty result set

## How this service works

One MCP endpoint gives your AI agent access to 100 APIs -- crypto, DeFi, web, AI, finance and utilities. No API keys, USDC on Base from $0.003/call.

## Output

Returns an ordered list of the top-K most semantically similar documents (or document chunks) from the indexed set, along with relevance/similarity scores, matched text content, and their position in the original document array.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "topK": {
   "type": "number",
   "description": "Number of top results to return (default: 3, max: 10)"
  },
  "query": {
   "type": "string",
   "description": "The text query to search for"
  },
  "documents": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "description": "Array of text documents to index (optional if already stored in this session)"
  },
  "namespace": {
   "type": "string",
   "description": "Namespace to isolate document sets (default: 'default')"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/klymax402-vector-search-api-55c13cee/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from klymax402.com](https://www.zero.xyz/host/klymax402.com/llms.txt)