# API Contracts and Dependency Boundaries

*MuleSoft Platform Architect Study Guide · Designing and sharing APIs · Last updated November 13, 2026 · https://www.certifyforce.com/study-guide/mulesoft-platform-architect/designing-and-sharing-apis/api-contracts-and-dependency-boundaries*

Trace the contract, repository dependency and implementation separately, then identify which teams must act when each changes. Use Studio's design tools without confusing a specification reference with application code.

- Certification: Salesforce MuleSoft Platform Architect
- Exam section: Designing and sharing APIs
- Study guide: https://www.certifyforce.com/study-guide/mulesoft-platform-architect

**Official exam objective:**

> Identify dependencies between an API, its API specification, its implementation, and its clients.

## What the exam expects

- Trace the dependency from a consumer's observable contract to the provider implementation.
- Predict what publishing a specification changes in an existing Studio project.
- Distinguish private implementation changes from consumer-facing contract changes.
- Choose the appropriate specification project or dependency workflow for the work required.

An **API contract** describes the exposed interface and behavior; a **specification** records that description; an **implementation** realizes it; a **dependency** identifies an artifact a project uses; a **consumer** invokes the exposed API.

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Exchange import | The Mule project references the selected specification version. | [Studio workflow](https://docs.mulesoft.com/studio/api-development-studio) |
| New publication | Studio can notify the developer of an available newer version. | [Studio workflow](https://docs.mulesoft.com/studio/api-development-studio) |
| Conformance | The implementing application must realize its selected specification. | [Studio workflow](https://docs.mulesoft.com/studio/api-development-studio) |
| Compatibility | Evaluate whether the exposed change requires consumer adaptation. | [Version guidance](https://docs.mulesoft.com/exchange/to-change-raml-version) |
| Local RAML | Reimport an externally updated local-copy specification. | [Studio workflow](https://docs.mulesoft.com/studio/api-development-studio) |
| Design inspection | The API Console lists summary, endpoints/methods and defined types. | [Console](https://docs.mulesoft.com/studio/test-specification-api-console) |
| Simulator configuration | Enabling Studio mocking leaves `baseUri` unchanged. | [Console](https://docs.mulesoft.com/studio/test-specification-api-console) |
| Request preparation | The selected endpoint populates Request URL. | [Console](https://docs.mulesoft.com/studio/test-specification-api-console) |

## Check yourself

- Why can a Studio design-project simulation retain the specification's original address declaration?
- When a synchronized specification project is ready for simulation, which explorer action enables the service?
- Which API Console field adds specific parameters to a test request?

## Sources

- [API Development in Studio](https://docs.mulesoft.com/studio/api-development-studio)
- [Changing the Version of an API Asset](https://docs.mulesoft.com/exchange/to-change-raml-version)
- [Test Your API Specification Using the API Console](https://docs.mulesoft.com/studio/test-specification-api-console)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 2 linked practice questions, and unlimited timed mock exams are included with the MuleSoft Platform Architect pack (USD $19): https://www.certifyforce.com/practice-exams