> ## 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.

# Circuit Breaker Tripped

> How to diagnose why a circuit breaker tripped, investigate the root cause, and reset it safely.

## What does a tripped circuit breaker mean?

When an agent's circuit breaker is active, every validation request returns a `403` response with `blockReason: "circuit_breaker_active"`. All transactions are blocked until the owner resets it. There is no automatic reset. This is intentional: a circuit breaker trip is a security event that requires human investigation.

## Step 1: Determine how it was tripped

There are two ways a circuit breaker trips.

### Manual trip

The owner activated it from the dashboard. Check the audit log for a `circuit_breaker_activated` event with `actor: owner`. This is a deliberate action, typically to pause an agent during maintenance or after observing suspicious behavior.

### Auto-trip (envelope mismatch)

The envelope verifier detected that the on-chain transaction does not match the parameters validated by Mandate. This is serious. It means the agent broadcast a transaction with different parameters than what was approved.

Check the audit log for a `circuit_breaker_auto_tripped` event. The event metadata includes:

* The validated parameters (to, calldata, value, gas)
* The on-chain parameters
* Which fields differ

## Step 2: Investigate the cause

### If manually tripped

Confirm with the owner why they tripped it. If it was for maintenance, you can reset it once the maintenance is complete.

### If auto-tripped (envelope mismatch)

This requires investigation. Common causes:

**Nonce collision.** The agent validated a transaction, then sent a different transaction with the same nonce before broadcasting the validated one. The validated intent's nonce was consumed by the other transaction. When the agent broadcast the validated transaction, it used a new nonce, causing a mismatch.

**Gas repricing.** The agent re-estimated gas after validation and broadcast with different gas parameters. The envelope verifier compares exact values.

**Middleware modification.** A signing middleware or wallet provider modified the transaction parameters between validation and broadcast. Some wallet libraries add safety margins to gas estimates.

**Malicious behavior.** The agent intentionally broadcast a different transaction than what was validated. This is the attack the circuit breaker is designed to catch.

<Warning>
  If the mismatch is caused by malicious behavior, do not reset the circuit breaker. Review the agent's code and access permissions before taking any action.
</Warning>

## Step 3: Reset the circuit breaker

Once you have identified and resolved the root cause:

1. Open the Mandate dashboard at `https://app.mandate.md`.
2. Navigate to the agent's detail page.
3. Toggle the circuit breaker to inactive.
4. Verify the agent can validate transactions again.

You can also reset via the API:

```bash theme={null}
curl -X POST https://app.mandate.md/api/agents/{agentId}/circuit-break \
  -H "Authorization: Bearer <sanctum-token>" \
  -H "Content-Type: application/json" \
  -d '{"active": false}'
```

## Step 4: Prevent future trips

* Use the SDK's `MandateWallet` class, which handles the validate-sign-broadcast-postEvent flow atomically with consistent parameters.
* Do not re-estimate gas between validation and broadcast.
* Do not modify transaction parameters after validation.
* Avoid sending other transactions between validation and broadcast if using sequential nonces.

## Next Steps

<CardGroup cols={3}>
  <Card title="Circuit Breaker Security" icon="power-off" href="/security/circuit-breaker">
    How the circuit breaker protects against unauthorized transactions.
  </Card>

  <Card title="Envelope Verification" icon="file-shield" href="/security/envelope-verification">
    How Mandate verifies on-chain transactions match validated intents.
  </Card>

  <Card title="Dashboard Circuit Breaker" icon="toggle-on" href="/dashboard/circuit-breaker">
    Manage circuit breaker state from the dashboard.
  </Card>
</CardGroup>