TxSim Decoder
Nine live x402 APIs for AI agents: web access, token safety, chain data, search, video, transaction simulation. Pay per call in USDC on Base, no API key.
DataLiveeip155:8453Exactvia cdp
Tx-simulationEth-callCalldataSecurityEvm
Calls · 30d
2
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 7 snapshots so far.
$40.91
Verified settled volume
4,161 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0050
Listed price
As published in the catalog. Always read the live 402 before paying.
2
Calls · 30d
Upstream's own call count for this endpoint, not ours.
2
Unique payers · 30d
Last called 2026-10-21 20:16Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x058D0Cc5CC97e61e8A9f38D6d6365bce525921B2The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Live 402 challenge
Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.
{
"pay": "curl -H 'X-Subscription-Key: cwx_...' 'https://simulate.cyberwarex.com/simulate'",
"price": "$0.005 per call. USDC on Base, no account, no API key, no signup.",
"trust": "https://cyberwarex.com/trust",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x058D0Cc5CC97e61e8A9f38D6d6365bce525921B2",
"amount": "5000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"catalog": {
"docs": "https://cyberwarex.com/llms.txt",
"services": "https://cyberwarex.com/.well-known/x402"
},
"featured": {
"url": "https://council.cyberwarex.com/council",
"deep": {
"url": "https://council.cyberwarex.com/council-deep",
"what": "4 models, 2 rounds, each seat sees the others and revises",
"price_usdc": 0.03
},
"docs": "https://cyberwarex.com/assets/council-quickstart.html",
"what": "a judgement call instead of a lookup: your question goes to several DIFFERENT AI models, a chair returns one verdict with confidence, the dissent and what would flip it",
"service": "Agent Council",
"try_free": "curl -H 'X-Free-Trial: 1' 'https://council.cyberwarex.com/council?q=YOUR+QUESTION'",
"use_when": "the next step is a decision rather than a fact - is this safe, is it worth it, which option",
"price_usdc": 0.01
},
"resource": {
"url": "https://simulate.cyberwarex.com/simulate",
"tags": [
"tx-simulation",
"eth-call",
"calldata",
"security",
"evm"
],
"iconUrl": "https://cyberwarex.com/assets/icon.png",
"mimeType": "application/json",
"description": "Simulate an EVM transaction before signing. Decodes the calldata into a named function with arguments and security risk flags, AND runs a keyless static eth_call preview to tell you whether the transaction would succeed or revert (with the decoded revert reason). Use it to catch a failing or malicious transaction before you broadcast it. Read-only, no keys, no node infra. Asset-level change tracing is v2.",
"serviceName": "TxSim Decoder"
},
"get_a_key": "pay once with any x402 client: POST https://safe.cyberwarex.com/subscribe?usd=3 -> {key: cwx_...} ($3 buys $3.30 of credit). One key works on every cyberwarex host, with no per-call signing.",
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"data": "0xa9059cbb000000000000000000000000d8da6bf26964af9d7eed9e03e53415d37aa960450000000000000000000000000000000000000000000000000000000005f5e100",
"from": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
"chain": "base"
}
},
"output": {
"type": "json",
"example": {
"to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"note": "asset-level change tracing requires a tracing RPC key (v2)",
"risk": {
"flags": [],
"level": "none"
},
"chain": "base",
"decoded": {
"args": {
"to": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
"amount": "100000000"
},
"function": "transfer",
"signature": "transfer(address,uint256)"
},
"disclaimer": "Static decode + keyless eth_call preview only. This is not financial advice and not a guarantee: a call that would succeed now can still revert at broadcast time (state changes, slippage, MEV). Always verify before signing.",
"asset_changes": null,
"revert_reason": null,
"would_succeed": true
}
}
},
"schema": {
"type": "object",
"$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",
"HEAD",
"DELETE"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"to"
],
"properties": {
"to": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Target contract or account address."
},
"data": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]*$",
"description": "Transaction calldata (hex)."
},
"from": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Sender address for the eth_call preview."
},
"chain": {
"enum": [
"base",
"ethereum",
"arbitrum",
"optimism",
"polygon",
"bsc"
],
"type": "string",
"default": "base",
"description": "EVM chain to simulate on."
},
"value": {
"type": "string",
"description": "Native value in wei (optional, decimal or 0x hex)."
}
},
"additionalProperties": false
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"properties": {
"to": {
"type": "string"
},
"note": {
"type": "string"
},
"risk": {
"type": "object",
"description": "level (none|caution|danger) + flags."
},
"chain": {
"type": "string"
},
"decoded": {
"type": "object",
"description": "function, signature, args."
},
"disclaimer": {
"type": "string"
},
"asset_changes": {
"type": "null",
"description": "v2: needs a tracing RPC key."
},
"revert_reason": {
"type": [
"string",
"null"
]
},
"would_succeed": {
"type": [
"boolean",
"null"
]
}
}
}
}
}
}
}
}
},
"quickstart": {
"node": "npm i @x402/fetch @x402/evm viem | import {wrapFetchWithPaymentFromConfig} from '@x402/fetch'; import {ExactEvmScheme} from '@x402/evm'; import {privateKeyToAccount} from 'viem/accounts'; const f = wrapFetchWithPaymentFromConfig(fetch, {schemes: [{network: 'eip155:8453', client: new ExactEvmScheme(privateKeyToAccount(PK))}]}); const r = await f(URL)",
"python": "pip install \"x402[evm,requests]\" | from eth_account import Account; from x402 import x402ClientSync; from x402.http.clients import x402_requests; from x402.mechanisms.evm import EthAccountSigner; from x402.mechanisms.evm.exact import ExactEvmScheme; c = x402ClientSync(); c.register('eip155:8453', ExactEvmScheme(EthAccountSigner(Account.from_key(PK)))); s = x402_requests(c); r = s.get(URL)",
"pay_with": "USDC on Base (eip155:8453); `accepts[0].amount` is in 6-decimal units (3000 = $0.003)"
},
"x402Version": 2,
"see_a_real_response": "GET https://simulate.cyberwarex.com/sample (free, no payment: one real answer from this service with its on-chain settlement tx)"
}Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.005USDC≈ $0.005 USD
on Base · exact scheme
Pay 0.005 USDC on Base to 0x058D…921B2. The signed payment is good for 5 minutes.
- Paid to
- 0x058D…921B2
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 5000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x058D0Cc5CC97e61e8A9f38D6d6365bce525921B2",
"amount": "5000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"data": "0xa9059cbb000000000000000000000000d8da6bf26964af9d7eed9e03e53415d37aa960450000000000000000000000000000000000000000000000000000000005f5e100",
"from": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
"chain": "base"
}
},
"output": {
"type": "json",
"example": {
"to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"note": "asset-level change tracing requires a tracing RPC key (v2)",
"risk": {
"flags": [],
"level": "none"
},
"chain": "base",
"decoded": {
"args": {
"to": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
"amount": "100000000"
},
"function": "transfer",
"signature": "transfer(address,uint256)"
},
"disclaimer": "Static decode + keyless eth_call preview only. This is not financial advice and not a guarantee: a call that would succeed now can still revert at broadcast time (state changes, slippage, MEV). Always verify before signing.",
"asset_changes": null,
"revert_reason": null,
"would_succeed": true
}
}
},
"schema": {
"type": "object",
"$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",
"HEAD",
"DELETE"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"to"
],
"properties": {
"to": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Target contract or account address."
},
"data": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]*$",
"description": "Transaction calldata (hex)."
},
"from": {
"type": "string",
"pattern": "^0x[a-fA-F0-9]{40}$",
"description": "Sender address for the eth_call preview."
},
"chain": {
"enum": [
"base",
"ethereum",
"arbitrum",
"optimism",
"polygon",
"bsc"
],
"type": "string",
"default": "base",
"description": "EVM chain to simulate on."
},
"value": {
"type": "string",
"description": "Native value in wei (optional, decimal or 0x hex)."
}
},
"additionalProperties": false
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"properties": {
"to": {
"type": "string"
},
"note": {
"type": "string"
},
"risk": {
"type": "object",
"description": "level (none|caution|danger) + flags."
},
"chain": {
"type": "string"
},
"decoded": {
"type": "object",
"description": "function, signature, args."
},
"disclaimer": {
"type": "string"
},
"asset_changes": {
"type": "null",
"description": "v2: needs a tracing RPC key."
},
"revert_reason": {
"type": [
"string",
"null"
]
},
"would_succeed": {
"type": [
"boolean",
"null"
]
}
}
}
}
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-10-21 20:16Z
- Last indexed by Roundhouse
- 2026-10-26 20:00Z
- Last enriched (probe, favicon, geo)
- 2026-10-21 06:45Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 7 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service TxSim Decoder and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=TxSim%20Decoder' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://simulate.cyberwarex.com/simulate, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.