# Cart Failure

### Failure scenario

The `cart` service has a feature flag `cartFailure` enabled that simulates Redis connection failures.

This causes the `EmptyCart` operation to fail with "Wasn't able to connect to redis" errors.

## Root Cause Analysis by Coroot

### How it works

#### 1. Anomaly detection

Coroot detected an anomaly in the `frontend-proxy` service, identifying increased latency and failed requests affecting the checkout flow.

#### 2. eBPF-based metrics correlation

Using eBPF metrics, Coroot traced the latency correlation across the entire request path, identifying the `cart` service as the bottleneck with EmptyCart operations taking 17+ seconds to fail.

#### 3. Understanding the cause

Coroot identified that the issue stems from a feature flag configuration in the `cart` service that simulates infrastructure failures for testing purposes. The EmptyCart operations fail with "Wasn't able to connect to redis" errors, causing timeout handling overhead and cascading delays through `checkout` → `frontend` → `frontend-proxy.

### Results

3/3

Detection of the problematic service:

Successfully identified the `cart` service as the source of Redis connection failures

Immediate fixes provided:

Recommended disabling the `cartFailure` feature flag to restore normal cart service operation

Additional details:

The analysis showed how the simulated Redis connection failures created a cascading latency problem throughout the entire checkout experience.

### LLM Usage Details

Model: Anthropic Claude Sonnet 4 (claude-sonnet-4-20250514)

Token usage: 43,186 input tokens • 761 output tokens

Estimated cost: ~$0.14 USD

Based on $3 per 1M input tokens, $15 per 1M output tokens