⚡
🧪 Simulate
LV3 · Ecosystem
Connected workflows and deeper Toolooo experiencesConnect it. Feature Level describes the depth of the tool experience.

Circuit Breaker Playground

See when a circuit breaker stops calls to a failing dependency and how it tests recovery.

EngineeringBackendReliabilityArchitecture
FAILURE CONTAINMENT LAB

Repeated failures open the circuit to protect the caller. A limited half-open probe tests whether requests can flow again.

60%
3 in a row
5 req
Result
Current state after 60 requests: Closed — requests allowed.
Why it matters
The breaker opened during the run, then successful probes closed it again. 20 historical blocked calls do not mean it is open now.
Action
Watch for renewed failures and compare policy trade-offs before changing thresholds.
  1. Closed →Allow calls; failures tripCurrent at end
  2. Open →Block calls; wait to probe
  3. Half-open →Probe passes: close. Fails: open.

Timeline: 60 request opportunities, not wall-clock seconds. Outcome cells show history; the current state above is the state after the last request.

SuccessFailureFast-rejected (circuit open)Half-open probeState strip: Closed / Open / Half-Open
Advanced: half-open probes & timed recovery
1 probe
Off (random)
POLICY COMPARISON
Run metrics & model limits
Current state
Closed
Requests fast-rejected
20
never touched the dependency
Recovery detection lag
Not detected / not configured
after the configured dependency recovery
State transitions
13
Trip trigger
3 consecutive failures
opened after request #3
Dependency calls avoided
20
fast-rejected by breaker
Without breaker
33 failed calls
vs 23 dependency failures with breaker
Open wait / probes
20 / 5
request opportunities open / half-open probes
Retry interaction
Off
Retry policy belongs in Retry Storm

A simplified model: one healthy probe closes the circuit again, and any single failed probe reopens it instantly.

A breaker does not repair a dependency. Thresholds are policy choices; real libraries may use rolling failure windows. Slow dependency models failure pressure, not latency. Retry counts are conceptual, not additional simulated requests.

What this tool does and why

Before you start

What

See when a circuit breaker stops calls to a failing dependency and how it tests recovery.

Why

Circuit-breaker thresholds and recovery rules decide whether a failing dependency is isolated or allowed to keep consuming resources.

Your Result and Action update in the tool as you change its inputs.

Model note

This browser-side model explains the inputs you choose. Check an important decision against the real system, brief, or production constraints.

Save this tool and explore next steps
My Toolooo
Saved only in this browser.
Resilient API traffic · Step 3 of 3

Stop calls to a failing dependency while it recovers.

How this tool stays honest

How it works

Compare failure containment policies across healthy, intermittent, outage, slow, and recovering dependency scenarios. Follow Closed, Open, and Half-Open states, see avoided dependency calls, and compare failure pressure with and without the breaker.

Assumptions

The tool runs in your browser and models the information you provide. It does not know facts outside that model.

Limitations

This is a simplified explanatory model, not a load test or production forecast. Real systems can include dependencies, distributions, failures, and feedback loops outside the selected inputs.

Understand Circuit Breaker Playground

What this tool helps you understand

Compare failure containment policies across healthy, intermittent, outage, slow, and recovering dependency scenarios. Follow Closed, Open, and Half-Open states, see avoided dependency calls, and compare failure pressure with and without the breaker.

When to use it

Before tuning isolation and recovery around a failing dependency.

Try a scenario

Trigger consecutive failures, then inspect the open and half-open transitions. Compare recovery thresholds without assuming they match a production library.

How to read the result

Compare the shape and direction of different scenarios. The useful signal is how the result changes when an input changes, rather than one isolated number.

Assumptions and limits

This is a simplified explanatory model, not a load test or production forecast. Real systems can include dependencies, distributions, failures, and feedback loops outside the selected inputs.