Feature

Request, contract, sequence

API monitoring for requests that can succeed and still break the contract.

PageLantern sends the real method, headers, body, and authentication, then checks status, latency, JSON expectations, schema, and ordered request flows before a bad response reaches customers.

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Authentication, headers, and payload flowing through an ordered API request chain into contract evidence.
Contract evidence: request shape, response assertions, timing, and captured variables.

Status contract fails

The endpoint returns a code outside the configured expectation.

Rejected

JSON assertion fails

A required response field is missing or contains the wrong value.

Invalid body

Request chain stops

A failing step ends the sequence before later requests can run.

Stopped

Requests and response contracts

Exercise the request shape, then prove the response is useful.

Single-request checks cover endpoint contracts. Multi-step checks share a session, capture values, and pass them into later URLs, headers, or bodies.

Request control

Send what the real client sends.

  • GET, POST, PUT, PATCH, DELETE, and HEAD
  • Headers, request body, and authentication profiles
  • Expected status, body text, and latency

Contract and flow

Validate more than transport success.

  • JSONPath assertions and JSON Schema
  • Up to 50 ordered API steps
  • Variable extraction between steps

Plan and location model: Single-request API checks and JSONPath assertions are on Free. Schema validation, multi-step flows, variable extraction, HAR export, and OpenAPI/Postman import start on Starter. Multi-step sequences run hub-local; single-request checks can use optional second-region failure confirmation.

Example result

Authentication worked. The contract still failed.

Illustrative values show where an ordered API flow stopped and which assertion caused it.

Flow
Create order
Steps
3
Captured
authToken
Expected
$.status = ready
Observed
pending
Outcome
Stopped at step 3

Next step

Turn the API contract into a scheduled proof.

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FAQ

Frequently asked questions

Can I monitor authenticated API endpoints?

Yes. API monitors send the method, headers, request body, and authentication profile that real clients use, so you exercise the same request shape your customers or internal services depend on.

What can PageLantern assert about an API response?

Beyond reachability, you can assert on status codes, response latency, body text, and specific JSON fields, so contract drift or missing data is visible even when the endpoint returns 200.

Which HTTP methods are supported?

API monitors support GET, POST, PUT, PATCH, DELETE, and HEAD, with custom headers and request bodies, so the check can match the endpoint’s real behavior instead of reducing it to a basic ping.