# x402-toolbox Chain Gas Estimator

> x402-toolbox Chain Gas Estimator is a paid API for AI agents from x402-toolbox.shablony-pro.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-02).

Estimates gas costs for a blockchain transaction on a specified chain schema via a pay-per-call x402 endpoint

## Facts

- Endpoint: GET https://x402-toolbox.shablony-pro.workers.dev/chain/estimate-gas?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-toolbox-chain-gas-estimator-b537a615
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_v-RY_R9bDWZh2hIF1Xspw

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 x402-toolbox-chain-gas-estimator-b537a615
```

Example prompt: Estimate the gas cost for a transaction using the 'erc20-transfer' chain schema — I want to know if it's affordable before I submit it on Base.

## When to prefer this

Choose this endpoint when you need a quick, no-signup gas estimate for EVM-compatible chains (especially Base) and are willing to pay $0.002 USDC per call via x402 micropayment. Ideal for AI agents that need deterministic, pay-as-you-go gas estimation without managing API keys or subscriptions.

## Known failure modes

- Invalid or unrecognized schema string returns an error or empty estimate
- Missing schema parameter may cause a 400 bad request
- Payment failure or insufficient USDC balance returns 402 Payment Required
- Network timeout from upstream RPC node causes delayed or failed response
- Unsupported chain schema returns an error

## How this service works

309 deterministic pay-per-call tools for AI agents over x402 (USDC, Base). No signup, no API key: the payment is the identity.

## Output

Returns a JSON object with an 'ok' boolean indicating success and a 'paid' boolean confirming x402 micropayment was processed, along with gas estimation data for the specified chain schema.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "schema": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "paid": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-toolbox-chain-gas-estimator-b537a615/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-toolbox.shablony-pro.workers.dev](https://www.zero.xyz/host/x402-toolbox.shablony-pro.workers.dev/llms.txt)