# Simulate Transaction

Use simulation to validate execution and estimate payable cost before submitting live execution.

## Endpoint

`POST /simulate`

## Authentication

`X-API-Key` required.

## Command

```bash
curl -X POST "$BASE_URL/simulate" \
  -H "Content-Type: application/json" \
  -H "X-API-Key: $API_KEY" \
  -d '{
    "agent_id": "my-agent-001",
    "chain": "ethereum",
    "target_contract": "0xTargetContract",
    "calldata": "0xCalldata",
    "value": "0"
  }'
```

## Success response

Status code: `200 OK`

Example:

```json
{
  "request_id": "your_request_id",
  "status": "pending",
  "smart_wallet_address": "0xAgentSmartWallet",
  "estimated_gas": 52000,
  "estimated_cost_usd": 0.23,
  "tx_hash": null,
  "message": "simulation succeeded"
}
```

## Cost semantics by payment mode

1. Manual includes platform fee.
2. Auto excludes platform fee.
3. Sponsored returns zero payable cost.

## Typical use

1. Call simulate first.
2. Validate gas and cost constraints.
3. Continue to execute only when output is acceptable.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.ardentresearch.xyz/request-api-key/simulate.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.