Building an Agent for Microsoft 365 Copilot: Adding an API plugin

In the previous post, we saw how to get started building agents for Microsoft 365 Copilot. We saw the different agent manifest files and how to configure them. There are some great out of the box capabilities available for agents like using Web search, Code Interpreter and Creating Images.

However, a very common scenario is to bring in data from external systems into Copilot and pass it to the LLM. So in this post, we will have a look at how to connect Copilot with external systems using API Plugins.

In simple terms, API Plugins are AI "wrappers" on existing APIs. We inform the LLM about an API and give it instructions on when to call these APIs and which parameters to pass to them. 

To connect your API to the Copilot agent, we have to create an "Action" and include it in the declarativeAgent.json file we saw in the previous post:

The ai-plugin.json file contains information on how the LLM will understand our API. We will come to this file later.

Before that, let's understand how our API looks. We have a simple API that can retrieve some sample data about repairs:

Next, we will need the OpenAI specification for this API

The OpenAPI specification is important as it describes in detail the exact signatures of our APIs to the LLM.

Finally, we will come to the most important file which is the ai-plugin.json file. It does several things. It informs Copilot which API methods are available, which parameters they expect and when to call them. This is done in simple human readable language so that the LLM can best understand it.

Additionally, it also handles formatting of the data before it's shown to the user in Copilot. Whether we want to use Adaptive Cards to show the data or if we want to run any other processing like removing direct links from the responses.

If you are doing plugin development, chances are that you will be spending most of your time on this file.

Once everything is in place, we will run our plugin with simple instructions and this is how it will fetch the data from external database

Hope this helps!

Create a Microsoft 365 Copilot plugin: Extend Microsoft 365 Copilot's knowledge

Microsoft 365 Copilot is an enterprise AI tool that is already trained on your Microsoft 365 data. If you want to "talk" to data such as your emails, Teams chats or SharePoint documents, then all of it is already available as part of it's "knowledge".

However, not all the data you want to work with will live in Microsoft 365. There will be instances when you want to use Copilot's AI on data residing in external systems. So how do we extend the knowledge of Microsoft 365 Copilot with real time data coming from external systems? The answer is by using plugins! Plugins not only help us do Retrieval Augmented Generation (RAG) with Copilot, but they also provide a framework for writing data to external systems. 

To know more about the different Microsoft 365 Copilot extensibility options, please have a look here: https://learn.microsoft.com/en-us/microsoft-365-copilot/extensibility/decision-guide

So in this post, let's have a look at how to build a plugin which talks to an external API and then infuses the real time knowledge into Copilot's AI. At the time of this writing, there is nothing more volatile than Cryptocurrency prices! So, I will be using a cryptocurrency price API and enhance Microsoft 365 Copilot's knowledge with real time Bitcoin and Ethereum rates!

(click to zoom)

So let's see the different moving parts of the plugin. We will be using a Microsoft Teams message extension built on the Bot Framework as a base for our plugin:  

1) App manifest

This is by far the most important part of the plugin. The name and description (both short and long) are what tell Copilot about the nature of the plugin and when to invoke it to get external data. We have to be very descriptive and clear about the features of the plugin here as this is what the Copilot will use to determine whether the plugin is invoked. The parameter descriptions are used to tell Copilot how to create the parameters required by the plugin based on the conversation.

2) Teams messaging extension code

This function does the heavy lifting in our code. It is called with the parameters specified in the app manifest by Copilot. Based on the parameters we can fetch external data and return it as adaptive cards. 

3) Talk to the external system (Cryptocurrency API)

This is helper function which is used to actually talk to the crypto api and return rates. 

Hope you found this post useful! 

The code for this solution is available on GitHub: https://github.com/vman/M365CopilotPlugin