API Security
API security starts with knowing what the interface exposes.
API security is not one scanner result. It is the discipline of understanding what an API exposes, who can call it, what each caller can do, which data can move through it, and which controls still need runtime evidence.
The security model
Think in layers, not in one score.
An API can be syntactically valid and still document risky access. It can also look clean in an OpenAPI contract while the runtime enforces authorization incorrectly. A useful review separates the declared interface from the deployed behavior instead of pretending either layer proves the other.
Contract
Operations, parameters, schemas, security requirements, scopes, servers, examples, and other declared behavior.
Runtime
Effective IAM, object-level authorization, network reachability, rate enforcement, business rules, and how the server actually handles input.
Change control
CI policies, review thresholds, capability deltas, and evidence retained when an API contract changes.
What OpenAPI can reveal
The contract gives you a map of the attack and capability surface.
OpenAPI can expose missing or optional authentication, broad permission labels, insecure server URLs, object identifiers, sensitive schemas, user-controlled URL-like inputs, destructive methods, and other review signals. Those signals are useful because they exist before production traffic is required.
That makes contract analysis valuable during design and pull-request review. It can tell a team where to look and what changed. It cannot confirm exploitability, prove object-level authorization, or demonstrate that a production gateway enforces the documented policy.
AI-connected APIs
Agents make legitimate API capability part of the threat model.
An AI agent does not need an implementation vulnerability to cause damage if it is intentionally given a legitimate operation such as issuing refunds, deleting users, rotating credentials, or exporting sensitive records. API security therefore includes understanding which operations become agent capabilities.
Before integration
Inventory the operations an agent could receive, narrow the allowed set, review authentication and permission metadata, and identify destructive or sensitive actions.
Secure AI agent API access →During change
Compare the baseline and candidate contract so new capabilities or authorization relaxations are visible in the same review loop as code changes.
API security in CI/CD →Start here
Use the contract as an early evidence layer.
Run the local OpenAPI scanner, then move into capability mapping and agent integration review when the API will be exposed to an AI system.
Turn the contract into evidence.
Run the local OpenAPI scanner, then use Agent Security when the API becomes an AI agent capability surface.