This page is intended for a user who has little to no experience with APIs, and provides a guided walkthrough for working with BCDA using our interactive documentation. More advanced API users may be better served by the Advanced User Guide. If you’re not sure where to go, start here!

Getting Started with APIs

  • What’s an API?
    • An API (Application Programming Interface) is a set of features and rules that exist inside a software program that allows other software programs to interact with it. For example, you can build an app that uses the Twitter API to get information or data from a user’s Twitter account. APIs are used in a wide variety of ways, but for our purposes, you can think of an API as a pipeline that can allow your ACO’s computer systems to receive data directly from CMS’ databases.
    • Need more information about APIs? Here are some great introductions:
  • Do I need to know how to code to use BCDA?
    • You do not need to know how to code! Our documentation is written so that everyone – regardless of technical exposure – can access beneficiary data. For this walkthrough, we’ll be using a platform called Swagger, where you’ll be able to interact with the API through a web interface.

Setting up your credentials in Swagger

To get to BCDA’s Swagger page for synthetic data, click on the following link, or copy and paste it into your web browser:

https://sandbox.bcda.cms.gov/api/v1/swagger

Walk-through: from credentials to token

Once the page is open, your first step will be getting an access token. You’ll use this access token later to prove you are allowed to use the API.

  • Find the section of the page shown below, in the auth category.
  • Click the lock icon.

Swagger: Auth category

In the sandbox environment, we provide generic credentials for you to use. These will not work in the production environment, but will allow you to explore the synthetic data in sandbox.

Client ID:

3841c594-a8c0-41e5-98cc-38bb45360d3c

Client Secret:

f9780d323588f1cdfc3e63e95a8cbdcdd47602ff48a537b51dc5d7834bf466416a716bd4508e904a

Back in Swagger, you’ll enter the client ID as the username, and the secret as the password.

  • Click the “Authorize” button when you’ve entered your credentials, then “Close”

Swagger: Authorize (1)

Now you’re ready to get a token!

  • To show more information about the /auth/token API endpoint, click on it (this time, away from the lock icon).
  • Click “Try it out”

Swagger: Token endpoint (1)

  • Click “Execute” to finally get your token

Swagger: Token endpoint (2)

If all is well, the Server response section will look similar to the following snapshot: it will have a response code of 200, and give an “access_token” in the response body.

  • Copy the access token. It will not have any spaces or newlines; the hyphens at the end of the lines are indicating that the line continues unbroken.

Swagger: Access token response

Now that you have a token, you can tell Swagger to use it for your future requests.

  • Find one of the the blue-colored bulk data API endpoints.
  • Click on the lock icon

Swagger: Coverage endpoint

In the “Value” box:

  • Type the word “Bearer” followed by a space
  • Paste your token
  • Click “Authorize” and then “Close”

Swagger: Authorize (2)

You are now ready to interact with the BCDA sandbox environment.

Making your first requests for data

1. Getting comfortable in Swagger

There are two categories of information that you can retrieve through BCDA: metadata, and bulk beneficiary data.

Swagger: metadata and bulkData

Metadata in BCDA includes information about the platform that is making, storing, and verifying credentials and tokens (the auth provider); information about the API’s version; and information about the actions you can perform using the API itself (also duplicatively termed metadata). There is no PII or PHI in the metadata endpoint, so you can access this endpoint without having to be authorized.

Swagger: metadata endpoints

2. Looking at BCDA Metadata

We’ll use auth as an example here.

Under the Metadata endpoint, click on /_auth to expand that section. After the information field expands, as shown below, click Try it out.

Swagger: Looking at BCDA Metadata (1)

Then, as shown below, click Execute to run the process of getting details about auth.

Swagger: Looking at BCDA Metadata (2)

As shown below, clicking Execute returns details about the authorization and authentication provider BCDA is using.

Swagger: Details about authorization and authentication

You can repeat this process with the /_version and /api/v1/metadata endpoints as well.

If you’d like to do this from the command line or implement this API call in code, look in the Curl section for the request you just made.

3. Learning about the Bulk Data Endpoints

The bulkData category provides information about beneficiaries. As shown below, there are five pieces of information within the bulkData category. The first three – Explanation of Benefit (EOB) data, Patient data, and Coverage data – are endpoints that return information about your ACO’s assigned or assignable beneficiaries. The last two pieces of information – jobId and filename – return information about the request you’re making.

  • Explanation of Benefit data includes claims data for your beneficiaries.
  • Patient data includes identification information about your assigned or assignable beneficiaries.
  • Coverage data includes each beneficiary’s Medicare coverage plan.

Swagger: Learning about the Bulk Data Endpoints

4. Making your first request for beneficiary data

To get any bulk beneficiary data, you must first be authorized with BCDA. Make sure you’ve followed the steps above for Setting up your credentials in Swagger before moving forward.

Retrieving beneficiary data comprises two steps:

  1. Starting a job to acquire data from a specific endpoint
  2. Retrieving data via a job request.

We’ll use the Coverage endpoint as an example of how to perform both steps. You’ll be able to follow the same instructions for Explanation of Benefit and Patient data as well.

First, click on GET /api/v1/Coverage/$export, then click Try it out.

Swagger: Coverage endpoint (1)

Then, as shown below, click Execute to start the process of requesting Coverage data. Make sure you note the job number (also known as jobId) in the response header, since you’ll need this job number to track the status of your data request.

Swagger: Coverage endpoint (2)

If you’d like to use the command line or implement this API call in code, look in the Curl section (shown in the image above) for the request you just made. Not far below that, you can see the response: an HTTP 202 Accepted giving a link in the content-location header for status information on your Coverage job.

5. Getting your data

There are three steps to retrieving the requested Coverage data:

  1. Checking the status of your job
  2. Downloading your bulk data file
  3. Decrypting your data file

Depending on the number of beneficiaries prospectively assigned or assignable to your ACO, it may take a while for your data file to be ready to download. While you wait, you can check the status of your job to find out when the file is ready.

You can check the status of the job by entering the job number into the jobId text field, as shown in the image below.

Swagger: retrieving your jobId

The X-Progress header indicates the job’s workflow status (Pending, In Progress, Completed, Archived, Expired, Failed). When in the In Progress state, an estimated completion percentage is appended to the X-Progress value (e.g., “In Progress (10%)”).

Once the job is completed, you will receive a HTTP 200 Complete response, which includes a URL ending in .ndjson, and an encryptedKey string. You’ll need the end of the URL in order to retrieve your data, and the encryptedKey in order to decrypt the file.

Swagger: retrieving your job info data

To retrieve your data, open the GET /data/{jobId}/{filename} endpoint. Copy the jobId into the jobId field, and the last string of the URL received in the previous step (highlighted in green and dashed lines above) into the filename field, then hit Execute.

Swagger: requesting your files

Click the Download file link that appears in the response section. Note that a large file may take a while to download.

Swagger: downloading your file

You will have twenty minutes before your token expires, and you will need to get another from token if it expires before you are finished interacting with the API.

The file you’ve downloaded will be encrypted. Follow the decryption walkthrough to learn how to decrypt and view the NDJSON data contained inside it.

Once you’ve decrypted the file, you’ll want to know what to do with the data. We’ve provided a guide to working with BCDA data to help you, including a crosswalk between CCLF fields and the corresponding sections of the NDJSON files.

Have questions?

The BCDA Google Group is the best place to get your questions answered by the BCDA team. In this community you can sign up for feedback session opportunities, get answers to your questions, share your feedback and ideas, and get updates on the project.

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