# Foundry Base Contract Fact Sheet

> Foundry Base Contract Fact Sheet is a paid API for AI agents from minty-sprout.onrender.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-11-01).

Returns raw on-chain facts about a Base network smart contract: proxy type, ownership, privileged powers in bytecode, ERC-20 token metadata, and current paused state — no verdict, just facts.

## Facts

- Endpoint: POST https://minty-sprout.onrender.com/v1/base-contract-facts?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/foundry-base-contract-fact-sheet-e2ed85cc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_uBm9yL7Ccq3R2URbh0Y2Y

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 foundry-base-contract-fact-sheet-e2ed85cc -d '<json body>'
```

Example prompt: Can you pull the on-chain fact sheet for the Base contract at 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 — I want to know if it's a proxy, who owns it, whether ownership is renounced, and what privileged powers like mint or pause are present in the bytecode?

## When to prefer this

Use this endpoint when you need raw, objective on-chain facts about a Base network contract with no opinion layer — ideal for pre-investment due diligence, automated token screening, proxy audit, or feeding structured contract data into a downstream risk-scoring agent. Prefer this over block explorer APIs when you need structured JSON with power detection, proxy type classification, and ownership flags in a single call.

## Known failure modes

- Invalid or non-hex address returns an error response
- Address is an EOA (not a contract) — is_contract=false, other fields absent
- Contract not deployed on Base mainnet — empty or error response
- Network or RPC timeout on the Base node — 5xx or timeout error
- Address is a contract but not ERC-20 — token fields will be null or absent
- Proxy implementation not readable — implementation address may be null

## How this service works

Base contract fact sheet from the chain: is it a contract, proxy type (EIP-1967, beacon, EIP-1167 clone, ZeppelinOS) with implementation and admin, owner and whether ownership is renounced or held by a contract (multisig) or single key, privileged powers found in bytecode (mint, pause, blacklist, fee/tax setters, trading switch, tx limits, upgrade), current paused state, ERC-20 name/symbol/decimals/supply. Facts only, no verdict. Input: 0x address.

## Output

A JSON object containing: whether the address is a contract, proxy type (EIP-1967, beacon, EIP-1167 clone, ZeppelinOS, or none) with admin and implementation addresses, owner address and flags for whether ownership is renounced or held by a contract vs EOA, list of privileged powers found in bytecode (mint, pause, blacklist, fee/tax setters, trading switch, tx limits, upgrade), current paused state, ERC-20 token name/symbol/decimals/total_supply, code size in bytes, and a list of plain-English observations highlighting notable risks or patterns.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "string",
   "maxLength": 8000,
   "description": "Base contract address, 0x + 40 hex characters"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "proxy": {
   "type": "zeppelinos",
   "admin": "0x4fc7850364958d97B4d3f5A08f79db2493f8cA44",
   "implementation": "0x2Ce6311ddAE708829bc0784C967b7d77D19FD779"
  },
  "token": {
   "name": "USD Coin",
   "symbol": "USDC",
   "decimals": 6,
   "total_supply": 4290041494.13
  },
  "paused": false,
  "powers": [
   "blacklist",
   "burn",
   "mint",
   "ownership",
   "pause",
   "upgrade"
  ],
  "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "control": {
   "owner": "0x3ABd6f64A422225E61E435baE41db12096106df7",
   "owner_is_contract": false,
   "ownership_renounced": false
  },
  "code_size": 1852,
  "is_contract": true,
  "observations": [
   "upgradeable proxy: logic can be replaced (admin is an externally owned account)",
   "owner-side mint function present: supply can grow",
   "pause function present: transfers can be frozen"
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/foundry-base-contract-fact-sheet-e2ed85cc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from minty-sprout.onrender.com](https://www.zero.xyz/host/minty-sprout.onrender.com/llms.txt)