# B20 Truth by ScriptMasterLabs

> B20 Truth checks who controls any Base B20 token. It reads Base's B20 precompiles live and reports which accounts can administer, mint, seize, pause, or block the token, plus pause state, supply cap, policy lists, and the genesis transaction. Built by Script Master Labs LLC (SDVOSB). Not affiliated with Base or Coinbase.

## What B20 is
- B20 is Base's native token standard (Beryl upgrade). Tokens are created by the factory precompile 0xB20f000000000000000000000000000000000000.
- Asset tokens start with 0xB200. Stablecoins start with 0xB201.
- B20 has built-in roles: DEFAULT_ADMIN, MINT, BURN, SEIZE, PAUSE, UNPAUSE, METADATA, OPERATOR (Asset).

## Verdicts
- LOCKED: no account holds any B20 role and no mutable policy list is attached.
- PARTIALLY_CONTROLLED: pause, policy-list, or metadata powers exist; no admin, mint, or seize.
- ISSUER_CONTROLLED: an account can administer, mint, or seize.

## Endpoints
- [Checker](https://b20.scriptmasterlabs.com/): free web checker; deep link /t/{address}
- [Free summary](https://b20.scriptmasterlabs.com/v1/check/{address}): verdict, powers, flags, genesis (rate limited)
- [Full report, x402](https://b20.scriptmasterlabs.com/v1/report/{address}): every role holder, policy admins, admin history; pay per call in USDC on Base via x402
- [MCP server](https://b20.scriptmasterlabs.com/mcp): streamable HTTP, tool `b20_check`
- [OpenAPI](https://b20.scriptmasterlabs.com/openapi.json)

## Method
- State: eth_call to B20 precompiles at a stated block number.
- Role holders: discovered from indexed RoleGranted/RoleRevoked events and the genesis caller, then each confirmed live with hasRole().
- Limits: describes onchain powers only. Not price, liquidity, or intent. Not financial advice.