Implicit invocation occurs when users invoke your app without using its name. This type of invocation occurs when users tell the Google Assistant to do something that's similar to the action invocation phrase for one of your configured intents, or when the user is in a context where your app would be appropriate.
Action discovery is a very powerful tool for getting your app in front of users. If a user wants to accomplish a task and your app has an action that can help the user with their task, the Google Assistant may recommend your app to the user.
This interaction occurs as follows:
- A user asks the Google Assistant to perform a task.
- The recommendation algorithm determines that your app has an action that can complete the user's task.
- The Assistant recommends your app to the user.
This interaction is much more likely when your app uses action invocation phrases that effectively bridge the gap between the user's choice of words and your app's intents. In practice, your app must serve a specific, useful purpose that real users ask the Google Assistant about in order for it to be discovered in this way.
Due to the evolving nature of the recommendation algorithm, Google cannot guarantee that your app will be recommended via action discovery. Keep the following best practices in mind when designing your app to improve the chance of your app being recommended:
Reduce conversational errors
Look for dead ends in your app's conversation to reduce the number of times your app errors out or forces users to quit.
Don't block your flow with Account Linking
Don't give users a required account linking prompt as the first thing your app does in its triggering intents. Give unauthenticated users a guest flow to show off the value of your action, then only ask for account linking if it's necessary to proceed.
Avoid open-ended questions
Questions like "what can I help you with" don't give the user context on how to proceed. Specific questions like "if you name a beach, I can give you a surf report" help keep the conversation moving.
Write useful action invocation phrases
If your action invocation phrases can't be mapped to a variety of related user queries, your app won't be recognized as relevant. Refer to the Writing useful action invocation phrases section for more details.
The Analytics > Discovery section of the Actions Console provides useful information about what phrases prompted the Google Assistant to recommend your app, and which of your app's actions was matched to the prompt.
You can find more information on our documentation about analytics and health.
Writing useful action invocation phrases
Action invocation phrases offer a helpful invocation and discovery tool for users, but you must choose them carefully. Keep the following best practices in mind when designing your action invocation phrases:
Keep your action invocation phrases specific to your app's use cases
Your app should serve a specific purpose , so make sure your action invocation phrases actually describe what your app does. For example, if your app is used to book flights, don't use "how do I get from $location to $location". A better alternative would be "book a flight from $location to $location".
Build phrases that include both a verb and an object
An invocation consists of a complete sentence, which means your action invocation phrase needs to be a verb-object pair in order to be linguistically natural. For example, "easy recipe" would be a bad action invocation phrase because the full invocation would be "Ok Google, easy recipe". A better alternative could be "how do I make an easy recipe" which could be invoked by "Ok Google, how do I make an easy recipe".
Consider the following examples of bad and good action invocation phrases:
Bad action invocation phrases
- Lacks a verb - "the number five"
- Too general - "travel to New York"
Good action invocation phrases
- Has a clear verb and object - "hear a dad joke"
- Provides specific requests:
- "what is my horoscope for today"
- "hear a fun fact"
- "give me a 5 minute workout"
- "what should I wear today"
- "get me a rental car"
- "I need a hotel room"
- "buy concert tickets"
- "coupons that expire today"
Of course, these action invocation phrases are not unique to your app and therefore the Assistant determines which apps to suggest for users
Adding action invocation phrases
In Dialogflow, your actions and their invocation phrases are defined as User Says expressions for triggerable intents, which can be configured in the Google Assistant integration within Dialogflow:
For more information, refer to the Dialogflow docs on Google Assistant integration.
In the Actions SDK, your actions and their invocation phrases are defined as query patterns. See the Actions SDK docs for more information.
In the Actions console, you can view your actions and their invocation phrases on the Overview page under Action discovery and re-engagement.
You can click on any of the actions listed to view their invocation phrases. If you're using Dialogflow, you'll have the option to Add more phrases, which links you directly to your app's intents in Dialogflow.