> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mandate.md/llms.txt
> Use this file to discover all available pages before exploring further.

# mandate validate

> Validate a transaction against your agent's policy. Supports preflight (action-based) and raw EVM modes.

## What does validate do?

The `validate` command checks a transaction against the policy engine before your agent signs anything. If the policy allows it, you get an `intentId`. If it blocks, you get a `blockReason`. If it requires approval, you get an `intentId` and a prompt to wait.

## Preflight mode (default, recommended)

Preflight validation is action-based. You describe what you want to do, and the policy engine evaluates it. No gas parameters, no calldata, no intentHash computation.

```bash theme={null}
npx @mandate.md/cli validate \
  --action transfer \
  --amount 50 \
  --to 0x036CbD53842c5426634e7929541eC2318f3dCF7e \
  --token USDC \
  --reason "Payment for API access"
```

### Options

| Flag       | Required | Description                                                |
| ---------- | :------: | ---------------------------------------------------------- |
| `--action` |    Yes   | Action type: `transfer`, `approve`, `swap`, or custom      |
| `--reason` |    Yes   | Plain-language explanation of why the agent is transacting |
| `--amount` |    No    | Amount in token units                                      |
| `--to`     |    No    | Destination address (0x...)                                |
| `--token`  |    No    | Token symbol (e.g. `USDC`) or contract address             |
| `--chain`  |    No    | Chain name or chain ID                                     |

### Success output

```json theme={null}
{
  "ok": true,
  "intentId": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "feedback": "Mandate: policy check passed"
}
```

### Blocked output

```json theme={null}
{
  "error": "POLICY_BLOCKED",
  "message": "Mandate: blocked: amount exceeds per-transaction limit",
  "blockReason": "SPEND_LIMIT_PER_TX"
}
```

The `blockReason` code tells you exactly which policy check failed. See the [block reasons reference](/reference/block-reasons) for the full list.

### Approval required

When the transaction triggers an approval workflow, the response includes the `intentId` and a next step:

```json theme={null}
{
  "ok": true,
  "requiresApproval": true,
  "intentId": "a1b2c3d4-...",
  "feedback": "Mandate: approval required, waiting for owner decision",
  "next": "Run: mandate approve a1b2c3d4-..."
}
```

Run `mandate approve <intentId>` to poll until the owner approves or rejects in the dashboard.

## The reason field

Every validation requires a `--reason`. This is not optional decoration. The policy engine scans the reason for prompt injection patterns, anomalous behavior, and policy violations. A clear, specific reason ("Payment for March invoice from Acme Corp") is more likely to pass than a vague one ("sending money").

<Warning>
  If you omit `--reason`, the command returns an error. The policy engine requires it for every transaction.
</Warning>

## Raw mode (legacy)

Raw mode sends full EVM transaction parameters and computes an `intentHash` locally. Use this only for self-custodial flows where you build the transaction yourself.

<Info>
  **Deprecated.** Use preflight mode instead. Raw validation is kept for legacy self-custodial flows but will be removed in a future version.
</Info>

```bash theme={null}
npx @mandate.md/cli validate --raw \
  --to 0x036CbD53842c5426634e7929541eC2318f3dCF7e \
  --calldata 0xa9059cbb000000000000000000000000 \
  --nonce 42 \
  --gasLimit 90000 \
  --maxFeePerGas 1000000000 \
  --maxPriorityFeePerGas 1000000000 \
  --reason "Invoice #127 from Alice"
```

### Raw mode required flags

| Flag                     | Description                        |
| ------------------------ | ---------------------------------- |
| `--raw`                  | Enable raw EVM validation          |
| `--to`                   | Contract or recipient address      |
| `--nonce`                | Transaction nonce                  |
| `--gasLimit`             | Gas limit                          |
| `--maxFeePerGas`         | Max fee per gas (wei)              |
| `--maxPriorityFeePerGas` | Max priority fee per gas (wei)     |
| `--reason`               | Why this transaction is being sent |

### Raw mode optional flags

| Flag           | Default          | Description               |
| -------------- | ---------------- | ------------------------- |
| `--calldata`   | `0x`             | Transaction calldata      |
| `--valueWei`   | `0`              | Value in wei              |
| `--chainId`    | From credentials | Chain ID                  |
| `--txType`     | `2`              | Transaction type          |
| `--accessList` | `[]`             | Access list (JSON string) |

Raw mode returns an additional `next` field pointing to the `event` command for posting the txHash after broadcast.

## Next Steps

<CardGroup cols={3}>
  <Card title="Transfer Command" icon="arrow-right" href="/cli/transfer">
    Shorthand for ERC20 transfers with automatic action mapping.
  </Card>

  <Card title="Wait for Approval" icon="arrow-right" href="/cli/approve">
    Poll until the owner approves a pending intent.
  </Card>

  <Card title="Validate Guide" icon="arrow-right" href="/guides/validate-transactions">
    End-to-end walkthrough of the validation flow.
  </Card>
</CardGroup>