# ChainK9 Transaction Preview & Token Risk Check

> ChainK9 Transaction Preview & Token Risk Check is a paid API for AI agents from api.chaink9.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-30).

Simulates a blockchain transaction on a forked chain sandbox to detect honeypots, balance changes, and token risks before execution on BNB Smart Chain, Ethereum, or Base.

## Facts

- Endpoint: GET https://api.chaink9.com/transaction-preview?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/chaink9-transaction-preview-token-risk-check-bcc0628f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZcoSJRlYWp7KvzOz69SGj

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 chaink9-transaction-preview-token-risk-check-bcc0628f
```

Example prompt: Before I buy this token on BSC, run it through ChainK9 and simulate the buy-and-sell using my wallet 0xABCDEF1234567890ABCDEF1234567890ABCDEF12 against the token contract 0x1234567890ABCDEF1234567890ABCDEF12345678 with the swap calldata 0xa9059cbb... — I want to know if it's a honeypot and what my BNB balance will look like after.

## When to prefer this

Choose ChainK9 Transaction Preview when you need behavioral honeypot detection — not just static code analysis — because it actually executes a buy and sell in a sandboxed fork, catching honeypots that pass code-level audits. Prefer this over static analyzers like Token Sniffer or Go+ Security when you need ground-truth simulation of balance changes and sell-ability. Ideal for trading bots and AI agents that need a pre-flight check before committing funds on BSC, Ethereum, or Base.

## Known failure modes

- Invalid wallet or contract address format returns a schema validation error
- Unsupported chain identifier returns an enum mismatch error
- Calldata that exceeds 16384 bytes is rejected
- Simulation may fail if the forked node cannot replicate mainnet state accurately at current block
- Token tracking list exceeding 10 addresses is rejected
- Network or RPC issues during fork simulation may cause timeouts
- x402 payment failure or insufficient USDC balance prevents the request from being processed

## How this service works

Token risk checks for BNB Smart Chain, Ethereum and Base, for AI agents and trading bots. ChainK9 forks the chain and really buys and sells a token in a sandbox before you do, so a honeypot is caught by what it does, not by what its code looks like.

## Output

Returns a JSON object with: transaction status (succeeded/failed), balance changes for tracked native and ERC-20 assets (before/after/delta), gas used, any token approval data, fork execution metadata (elapsed time, RPC calls, fork transaction count), block number simulated, chain ID, coverage notes, and any limits applied (e.g. fork-only constraints).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "wallet",
      "to",
      "data"
     ],
     "properties": {
      "to": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "Transaction target"
      },
      "gas": {
       "type": "string",
       "pattern": "^[0-9]{1,78}$",
       "description": "Optional gas limit, 21000 to 3000000"
      },
      "data": {
       "type": "string",
       "pattern": "^0x([0-9a-fA-F]{2}){0,16384}$",
       "description": "Transaction calldata, 0x for native transfer"
      },
      "chain": {
       "enum": [
        "bsc",
        "eth",
        "base",
        "arc"
       ],
       "type": "string",
       "description": "bsc (BNB Smart Chain, the default), eth (Ethereum) or base (Base)"
      },
      "value": {
       "type": "string",
       "pattern": "^[0-9]{1,78}$",
       "description": "Native coin wei (BNB or ETH), default zero"
      },
      "tokens": {
       "type": "string",
       "description": "Optional comma-separated ERC-20 assets to track, maximum ten"
      },
      "wallet": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "Sending EOA"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "cost": {
       "type": "object",
       "properties": {
        "elapsed_ms": {
         "type": "integer"
        },
        "local_rpc_calls": {
         "type": "integer"
        },
        "fork_transactions": {
         "type": "integer"
        }
       }
      },
      "data": {
       "type": "object",
       "properties": {
        "status": {
         "type": "string"
        },
        "approval": {},
        "coverage": {
         "type": "string"
        },
        "gas_used": {
         "type": "integer"
        },
        "balance_changes": {
         "type": "array",
         "items": 
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "cost": {
   "elapsed_ms": 1000,
   "local_rpc_calls": 10,
   "fork_transactions": 1
  },
  "data": {
   "status": "succeeded",
   "approval": null,
   "coverage": "Only supplied assets inspected.",
   "gas_used": 21000,
   "balance_changes": [
    {
     "after": "99",
     "asset": "BNB",
     "delta": "-1",
     "before": "100"
    }
   ]
  },
  "tool": "transaction-preview",
  "block": 1,
  "limits": [
   "Fork only."
  ],
  "chain_id": 56
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/chaink9-transaction-preview-token-risk-check-bcc0628f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.chaink9.com](https://www.zero.xyz/host/api.chaink9.com/llms.txt)