# exempt

URL: /business/nouns/customer/exempt · Id: `verb:Customer.exempt` · Call: `await $.Customer.exempt({ … })` (SDK) or the `do` tool at `https://api.sb/mcp`. Inputs says what to pass, Outputs what returns, When it waits who approves.

> Exempt records a Customer’s exemption or resale certificate, verifies it, and stops tax on its Orders where the certificate applies.

Exempt records a [Customer](/business/nouns/customer)’s exemption or resale certificate, verifies it, and stops tax on its [Orders](/business/nouns/order) where the certificate applies.

## Inputs
| Input | Type | Required | Description |
| --- | --- | --- | --- |
| `customer` | [Customer](/business/nouns/customer) | Yes | The buying Customer. |
| `certificate` | [File](/business/nouns/file) | Yes | The certificate as uploaded through the Portal or received by email. |
| `jurisdictions` | `string[]` | Yes | Where the certificate applies, such as `US-TX`. |
| `expiresOn` | `date` | No | When the certificate lapses; empty when it does not. |

## Outputs
| Output | Type | Required | Description |
| --- | --- | --- | --- |
| `credential` | [Credential](/business/nouns/credential) | Yes | The certificate, held by the Customer’s Organization. |
| `customer` | [Customer](/business/nouns/customer) | Yes | The Customer, now exempt where the certificate applies. |

## Effects
- Emits [`Customer.exempted`](/business/events/Customer.exempted).
- Performed by the [Finance Lead](/agents/finance/finance-lead).
- Two-way: it runs at once, in the `try`, `send` and `do` modes.
- Verifies the certificate number with the issuing authority where it offers a lookup.
- Every exempt Order carries the Credential in `taxExemption`.
- Asks the Customer for a new certificate 30 days before it lapses.

## Refuses when
| Check | Error | Fix | Then call |
| --- | --- | --- | --- |
| The key is valid, but its scopes do not allow this operation. | [`forbidden`](/code/api/errors/forbidden) | Use a key whose scopes cover the operation, or ask an owner of the namespace to grant them. | [Customer.exempt](/business/nouns/customer/exempt) |

## When it waits
| Gate | Default |
| --- | --- |
| Decision class | Low: two-way, nothing at stake |
| [Delay window](/systems/trust-and-governance/controls/one-way-windows) | None: it runs once review passes. |
| Limit | The call [Limit](/business/nouns/limit) of the [Permission](/business/nouns/permission) it runs under. |
| Over the Limit | It waits `pending` for an [Approval](/business/nouns/approval) from the [Founder](/agents/founding/founder). Approved, it runs; refused, it ends `refused` with [`limit-exceeded`](/code/api/errors/limit-exceeded); unanswered by its deadline, it ends `canceled`. |

## Example

**Ask**

```text
Exempt the latest customer with a file.
```

**API**

```bash
curl -X POST https://api.sb/ledgerlark.com/customers/customer_1/exempt \
  -H "Authorization: Bearer $STARTUP_BUILDER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"certificate":"file_1","jurisdictions":["US-TX"]}'
```

```json
{
  "api": "https://api.sb/ledgerlark.com",
  "credential": {
    "$id": "https://api.sb/ledgerlark.com/credentials/credential_1",
    "$type": "Credential",
    "issuer": "Example issuer",
    "jurisdiction": "US-DE"
  },
  "customer": {
    "$id": "https://api.sb/ledgerlark.com/customers/customer_1",
    "$type": "Customer",
    "since": "2026-10-22T12:00:00Z"
  },
  "action": {
    "$id": "https://api.sb/ledgerlark.com/actions/action_1",
    "operation": "Customer.exempt",
    "status": "done"
  },
  "links": {
    "self": "https://api.sb/ledgerlark.com/actions/action_1"
  }
}
```

**SDK**

```ts
import { $ } from 'startup-builder'

const { credential, customer } = await $.Customer.exempt({ customer: 'customer_1', certificate: 'file_1', jurisdictions: ['US-TX'] })
```

**CLI**

```bash
npx startup-builder do Customer.exempt --json '{"customer":"customer_1","certificate":"file_1","jurisdictions":["US-TX"]}'
```

**MCP**

```json
{
  "name": "do",
  "arguments": {
    "code": "return await $.Customer.exempt({ customer: 'customer_1', certificate: 'file_1', jurisdictions: ['US-TX'] })"
  }
}
```