# TrollBridge Transaction Dry-Run Simulator

> TrollBridge Transaction Dry-Run Simulator is a paid API for AI agents from mini-tollbooth.onrender.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-12).

Simulates a blockchain transaction before signing and returns a plain-English explanation of its effects plus a safety verdict (safe, review-carefully, or do-not-sign)

## Facts

- Endpoint: GET https://mini-tollbooth.onrender.com/tx-dryrun?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/trollbridge-transaction-dry-run-simulator-cf7a041c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oiCRj-x2OgLGqewoZARhn

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 trollbridge-transaction-dry-run-simulator-cf7a041c
```

Example prompt: Before I sign this transaction, simulate it and tell me in plain English what it does to my wallet — the target contract is 0xabc123…, calldata is 0xdeadbeef…, sending from 0xmywallet… on Base with 0 ETH value.

## When to prefer this

Use this endpoint when an AI agent or user needs to understand and vet a specific transaction before signing — especially when the calldata is opaque, the contract is unfamiliar, or approval grants are suspected. Prefer this over static contract analysis tools when you have actual calldata and want a simulation-based explanation of real on-chain effects rather than just code auditing.

## Known failure modes

- Missing required parameters (to, data, from) returns an error
- Invalid hex calldata format causes simulation failure
- Contract not deployed on specified chain returns revert or error
- Unsupported chain value (not 'base' or 'ethereum') rejected
- RPC node unavailability causes simulation timeout
- Payment of $0.02 USDC not provided results in 402 Payment Required

## How this service works

The insurance booth for AI agents, with Mini's Agent Supply Store on the side of the road. One hundred checkpoints: pre-transaction safety lanes (honeypot, approval-risk, rug-score, receipt-check, tx-dryrun, permit-scan, airdrop-verdict, deployer-history, wallet-watch, secret-scan at $0.02 USDC per call; the protection tier — /contract-check, /approval-screen, /tx-plain-english, /honeypot-check, /tx-simulate, /redteam, /skill-scan, /verdict, /egress-audit, /tool-gate, /airlock, /repo-scan, /prove, /task-scope — at $0.10; the one-call /shield don't-get-rugged screen at $0.25; the full /preflight bundle at $0.05), bounty intel (bounties, fresh, verdicts, deadlines, sweepstakes, opportunities) at $0.02 USDC per call, trader intel (/prices and /quant at $0.02; /enrich and /token-check at $0.05; /contract-check and /honeypot-check at $0.10; /sec-facts at $0.05), market intel (/markets and /search at $0.05; /grants at $0.02), DeFi intel (/yields and /new-pairs at $0.05; /gas and /defi at $0.02), AI intel (/models at $0.02), agent-ops intel (/prompt-cost, /model-picks, /rpc-speed, /terms-tldr, /scrape, /gigs, /retry-verify, /idempotency, /verify-independent at $0.02; /site-watch, /wallet-check, /code-run, /regulatory-pack, /sage, /cron-watch, /caveat-check, /tripwire, /escrow, /trust, /bridge-fees, /dao-votes, /dev-activity, /dex-arb, /dydx-perps, /funding-rates, /gas-predict, /hack-tracker, /long-short-ratio, /lp-yields, /mev-scan, /open-interest, /perp-basis, /polymarket-odds, /rwa-watch, /sentiment, /stablecoin-flows, /tokenomics, /top-movers, /whale-watch, and /yield-stable at $0.05; /approval-screen, /tx-plain-english, /tx-simulate, and /task-scope at $0.10; /scam-scan deep scan at $5.00 or 30-day subscription at $30.00), supply store (/road-pack combo meal at $0.05; curated datasets, the /audit-prep pre-audit review, and the /prove-state symbolic-execution run at $1.00; the /audit AI-agent audit at $25.00). Every lane answers before money moves — heuristic verdicts, not audits. Don't get rugged.

## Output

A JSON object containing: the simulation outcome (whether the transaction reverted), a plain-English explanation of exactly what the transaction does (decoded approvals, token transfers, swaps), and a safety verdict of 'safe', 'review-carefully', or 'do-not-sign'. Also echoes back the to/from addresses, chain, and lane for traceability.

## 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": [
      "to",
      "data",
      "from"
     ],
     "properties": {
      "to": {
       "type": "string",
       "description": "Target contract address the transaction calls (0x… on Base or Ethereum)."
      },
      "data": {
       "type": "string",
       "description": "Hex calldata of the transaction (0x…)."
      },
      "from": {
       "type": "string",
       "description": "Wallet address that would send the transaction (0x…)."
      },
      "chain": {
       "enum": [
        "base",
        "ethereum"
       ],
       "type": "string",
       "description": "Which chain (default base)."
      },
      "value": {
       "type": "string",
       "description": "Native currency value in wei, decimal or 0x… hex (default 0)."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "to": "0x...",
  "from": "0x...",
  "lane": "/tx-dryrun",
  "chain": "base",
  "verdict": "review-carefully",
  "simulation": {
   "reverted": false
  },
  "description": "NOT AN AUDIT — simulation, not a guarantee: the crystal ball — simulate any transaction before signing and get a plain-words explanation of what it does to your wallet (approvals, transfers, swaps decoded). Verdict: safe, review-carefully, or do-not-sign.",
  "explanation": "This grants 0x… unlimited rights to move your USDC."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/trollbridge-transaction-dry-run-simulator-cf7a041c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mini-tollbooth.onrender.com](https://www.zero.xyz/host/mini-tollbooth.onrender.com/llms.txt)