THE INTEGRATION FAILURE LAB

Make your integrations fail on purpose.

Hosted mock APIs for testing CRM writes, lead ingestion and AI clients. Choose provider-shaped failures, then inspect the requests your integration sends.

Test third-party integrations without depending on third parties.

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Real requests. Real responses. Not the real API.

SYNTHETIC ILLUSTRATIVE EXAMPLE

YOUR APPNOTTHEREALAPIPROVIDER SIM

illustrative request / response

POST/services/data/v66.0/sobjects/Lead/

SELECTED SCENARIOAPI allocation exhaustedSalesforce simulation · repeatable

RESPONSE403 Forbidden

HTTP/1.1 403 Forbidden
content-type: application/json; charset=utf-8

[
  {
    "message": "API request limit exceeded",
    "errorCode": "REQUEST_LIMIT_EXCEEDED",
    "fields": []
  }
]

Illustration only; no live request captured

CONTROL THE RESPONSECAPTURE TEST REQUESTSREPEAT THE FAILUREINSPECT THE EVIDENCE

ONE FAILURE, END TO END

Test Marketo daily quota exhaustion: body code 607.

On an installed synthetic receiver, select Marketo Leads → Sync Lead → Daily API quota reached. Send a safe lead sync, read the selected response, then inspect the captured request in your workspace.

HTTP 200 can still carry a business failure. Check the body, avoid immediate retries for exhausted daily allocation, and test success separately.

HTTP 200
content-type: application/json

{
  "requestId": "example#1",
  "success": false,
  "errors": [
    {
      "code": "607",
      "message": "Daily quota reached"
    }
  ]
}

Synthetic illustrative example, not a live capture. The full walkthrough shows placeholder curl and PowerShell requests and illustrative inspection.

Follow the Marketo 607 walkthrough →

THE WORKFLOW

External APIs don’t have to cooperate with your test plan.

Point your client at a synthetic endpoint. Choose the response you need. Inspect what your integration actually sent and what it received.

01 / INSTALL

↗

Install the API

Choose the provider API module and point your development integration at its stable endpoint.

POST /services/data/v66.0/…

02 / CONTROL

⎇

Switch its behaviour

Choose success, auth failure, rate limiting or a controlled error without reinstalling the module.

response: REQUEST_LIMIT_EXCEEDED

03 / EVIDENCE

⌁

Inspect the request

Read captured paths, headers, bounded payloads and synthetic responses in one place.

403 REQUEST_LIMIT_EXCEEDED

FAILURE, ON DEMAND

Test the cases you hope never happen.

Install a provider API module once, switch its behaviour whenever you need a new outcome, and inspect what your integration sent. Generic Mock remains available for your own HTTP behavior.

OpenAI · Responses API provider-shaped200

POST /v1/responses

Streaming response

Consume text deltas and handle stream completion or interruption.

RESPONSE200 / text/event-stream

Salesforce provider-shaped401

POST /services/data/v66.0/sobjects/Lead/

Authentication failure

Exercise token refresh before production does.

RESPONSE401 / INVALID_SESSION_ID

Generic Mock custom HTTP422

POST /v1/orders

Custom validation response

Return the exact response your client should handle.

RESPONSE422 / your chosen body and headers

NotTheRealAPI independently simulates third-party APIs for testing. All provider names and logos are the property of their respective owners. NotTheRealAPI is not affiliated with, sponsored by or endorsed by those providers, and these modules do not connect to their live services. Twilio and all related logos are trademarks of Twilio Inc. or its affiliates.

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ONE PLAN. A CLEAR PRICE.

Build confidence before you ship.

Spend less time writing provider-shaped fixtures. Combine selected failures, custom HTTP responses and shared request inspection in one team workspace.

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Up to 5 active workspace members
10 environments · 50 endpoints
100,000 requests/month
10,000 latest captures · up to 30 days, subject to rotation and scheduled cleanup

Debugging an empty Dataverse response or an incomplete AI stream? Read the developer troubleshooting guides for repeatable tests and client assertions.

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