How do you prove a vulnerability is exploitable and not theoretical?

Each finding comes with a working proof of concept: the exact request that triggered it, the response that confirms it, and reproduction steps. Unverified flags never reach your queue.

Which API styles do you test?

REST, GraphQL, and gRPC, authenticated or not. Agents can load an OpenAPI or GraphQL schema, discover endpoints from the live service, or read them from source.

How do you test authorization across users and tenants?

Give the agents credentials for the roles you care about. They replay requests as each one, swap identifiers and tokens, and report every case where an endpoint returns or changes data the caller should not reach, with the request and response as proof.

Do you need our OpenAPI spec?

It helps but is not required. A spec gives agents a complete endpoint list on day one. Without one they discover the surface from the running service, and from source if you connect a repository.

How is this different from an API scanner?

A scanner sends known payloads to the endpoints in your spec and flags suspicious responses. The agents reason about your API across requests and roles, which is where most real API flaws are, and report a finding only after exploiting it.

How do you test rate limits and logic without harming production?

With ordinary call patterns, never floods. Agents confirm a vulnerability and stop, take no destructive actions, respect the scope you set, and log every request they make.

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Real vulnerabilities, found and proven.

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Only the reachable dependency risks.

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Vulnerabilities caught before they merge.

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Research, writeups, and product news.

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How we secure the agents and your data.

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API security testing thatproves every finding.

Agents load your API from a spec or the live service, then replay and tamper with requests across users and tenants to find what one endpoint leaks to another.

See first findings in 24 hours

API styles: REST, GraphQL, gRPC

24h

to first findings

<1%

false positives

Built by the team that secured:

[ how it works ]

How API securitytesting works.

Load the surface

Import an OpenAPI or GraphQL schema, point agents at the live service, or connect the repo. Every endpoint, parameter, and role boundary is catalogued.

Attack across roles

Agents replay requests as different users and tenants, tamper with identifiers and tokens, and chain calls between endpoints.

Prove and prioritise

Each finding ships with the request that triggered it, the response that proves it, a CWE tag, and guidance for the owning team.

[ coverage ]

The API flaws a scannercannot reason about.

Most API vulnerabilities are about who may call what with which identifier. Finding them takes reasoning across requests.

Broken object-level authorization

IDOR across users and tenants: swapping identifiers to read or change someone else's records.

Broken authentication

Token handling, session logic, key leakage, and endpoints that answer without the credentials they should demand.

Function-level access control

Admin and internal operations reachable by ordinary roles, or by no role at all.

Injection and SSRF

Injection through parameters and payloads, and server-side requests an attacker can steer.

Mass assignment and data exposure

Fields that should never be writable, and responses that return more than the caller should see.

Business logic

Rate limits, workflow order, and pricing or quota rules that can be abused with legitimate calls.

[ compare ]

API scanner, manual test,or Parameter.

Where each approach gets its list of endpoints, and what it can say about them.

API scanner

Manual API pentest

Parameter

Discovery

The spec you upload.

The endpoints there is time to look at.

Spec, live traffic, and source, re-mapped as the API changes.

Authorization testing

Limited, usually single-role.

Thorough for the roles the tester is given.

Every role and tenant, replayed against every endpoint.

Validation

Flags to triage.

Manual proof for reported findings.

Every finding reproduced with the request and response.

Cadence

Scheduled.

Per engagement.

Every release, and on demand.

Discovery

API scanner

The spec you upload.

Manual API pentest

The endpoints there is time to look at.

Parameter

Spec, live traffic, and source, re-mapped as the API changes.

Authorization testing

API scanner

Limited, usually single-role.

Manual API pentest

Thorough for the roles the tester is given.

Parameter

Every role and tenant, replayed against every endpoint.

Validation

API scanner

Flags to triage.

Manual API pentest

Manual proof for reported findings.

Parameter

Every finding reproduced with the request and response.

Cadence

API scanner

Scheduled.

Manual API pentest

Per engagement.

Parameter

Every release, and on demand.

[ definition ]

What is API security testing?

API security testing checks the endpoints an application exposes, whether REST, GraphQL, or gRPC. The common flaws are broken authorization, weak authentication, injection, and data exposure. Parameter's agents load the API from a spec or the live service. They replay requests as different users and tenants, and prove each finding with the request that triggered it.

[ FAQ ]