# Synapse API — Kaia Blockchain RPC

> Synapse API — Kaia Blockchain RPC is a paid API for AI agents from synapse-api-brown.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Provides a pay-per-call JSON-RPC gateway to the Kaia (formerly Klaytn) blockchain network, enabling queries and interactions with Kaia chain state.

## Facts

- Endpoint: POST https://synapse-api-brown.vercel.app/api/kaia/rpc
- 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/synapse-api-kaia-blockchain-rpc-9ff20f63
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jLtDcJVWuOmzak8JWaCN8

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 synapse-api-kaia-blockchain-rpc-9ff20f63 -d '<json body>'
```

Example prompt: Can you check the current block number on the Kaia blockchain by calling eth_blockNumber via the Kaia RPC endpoint?

## When to prefer this

Choose this endpoint when you specifically need to interact with the Kaia (formerly Klaytn) blockchain network via standard JSON-RPC calls, especially in a pay-per-call context without needing a dedicated node or API key subscription. Prefer this over self-hosted nodes when you want low-overhead, on-demand access to Kaia chain data for agents or automation workflows.

## Known failure modes

- Invalid JSON-RPC method name returns error code -32601 (Method not found)
- Malformed params array causes -32602 (Invalid params) error
- Network congestion may cause timeouts on heavy queries
- Payment failure (402) if x402 micropayment not included or insufficient
- Kaia node unavailability returns 503 or connection error
- Submitting an invalid or malformed raw transaction returns execution revert or bad request error

## How this service works

High-speed API suite for AI processing, web scraping, and smart data utilities across 57+ blockchain networks. Pay-per-call via x402.

## Output

Returns a standard JSON-RPC response object containing the result of the requested Kaia blockchain method call, such as block data, account balances, transaction receipts, or smart contract return values. Errors are returned as JSON-RPC error objects with code and message fields.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "method": {
   "type": "string"
  },
  "params": {
   "type": "array",
   "items": {}
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synapse-api-kaia-blockchain-rpc-9ff20f63/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from synapse-api-brown.vercel.app](https://www.zero.xyz/host/synapse-api-brown.vercel.app/llms.txt)