Skip to content

Fail-Closed Architecture

When In Doubt, Deny.

Most authorization systems fail open — when they go down, everything gets through. Intended fails closed. If the authority service is unreachable, no AI agent action executes. Period.

The Critical Question

What happens when your authorization system goes down?

Toggle the simulation below to see how fail-open and fail-closed architectures respond to the same outage.

Fail-Open System

Auth service unreachable
Fallback: skip authorization
Agent deploys to production
Agent modifies customer records
Agent processes $50k payment
No audit trail captured

Fail-Closed (Intended)

Auth service unreachable
Fail-closed: DENY all actions
Deploy blocked — queued
Record modification blocked
Payment blocked — queued
Operators notified via alert

Defense in Depth

Every boundary is fail-closed

Four independent boundaries, each with its own fail-closed gate. A failure at any point blocks the action.

01

API Gateway

Validates request format and authentication. Rejects malformed requests.

Fail-closed
02

Intent Compiler

Classifies the action. If classification fails, action is denied.

Fail-closed
03

Authority Engine

Evaluates policies. If unavailable, the default decision is DENY.

Fail-closed
04

Execution Gateway

Verifies authority token. No valid token means no execution.

Fail-closed

The Rule

No token, no execution

The execution gateway requires a valid, unexpired, single-use authority token before any action proceeds. There are no exceptions, no bypass flags, and no override modes.

if(!token || !token.valid || token.expired || token.nonceUsed)
DENY— action blocked, event logged, alert sent

Recovery

Self-healing recovery

When the authority service recovers from an outage, queued actions are re-evaluated against current policies. Nothing slips through the cracks, and no action is permanently lost.

During outage

Actions queued

On recovery

Re-evaluated

Result

Zero data loss

Authorization that never fails silently.

Free to start. No credit card required.