Skip to main content

12. API Management and Gateway

This section defines the role of API Management and gateway components in exposing capabilities, enforcing contracts, and applying governance controls without embedding business logic.

12.1 Role of API Management​

API Management provides a controlled ingress point into the capability layer.

Its responsibilities include:

  • Exposing capability endpoints
  • Enforcing authentication and authorisation
  • Applying policies consistently
  • Providing observability and usage metrics

API Management does not:

  • Implement capability logic
  • Orchestrate workflows
  • Transform domain semantics

It acts as a policy and control plane, not an execution engine.

12.2 Capability Exposure​

Capabilities are exposed through API Management as:

  • Versioned endpoints aligned to capability contracts
  • MCP-compatible interfaces where applicable
  • Deterministic and AI-assisted execution paths behind a common façade

Exposure rules:

  • One endpoint per capability version
  • No leakage of underlying system interfaces
  • Explicit mapping to execution services

Consumers interact with capabilities, not systems.

12.3 Versioning and Deprecation​

API Management enforces capability versioning and deprecation policies.

Versioning:

  • Aligns with capability contract versions
  • Allows parallel operation of multiple versions
  • Requires explicit consumer selection

Deprecation:

  • Is time-bound and communicated
  • Does not break existing consumers abruptly
  • Is enforced through policy, not code changes

This ensures evolution without disruption.

12.4 Throttling and Quotas​

Throttling and quotas protect the architecture from overload and cost escalation.

Controls include:

  • Per-consumer rate limits
  • Per-capability quotas
  • Execution-mode–specific limits (e.g. stricter limits for AI-assisted execution)

Limits:

  • Are transparent to consumers
  • Are configurable by policy
  • Support burst handling where appropriate

This ensures predictable performance and cost control.

12.5 Policy Enforcement​

Policies are applied uniformly at the gateway.

Policy types include:

  • Security policies (auth, authz)
  • Execution policies (allowed execution modes)
  • Compliance policies (data handling, logging)
  • Cost and usage policies

Policies:

  • Are declarative and centrally managed
  • Do not require redeployment of executors
  • Are auditable and testable

This enables strong governance without slowing delivery.