[GPTs] A Thorough Explanation of the Mysterious "Actions" Feature! Evolve Your AI into the "Ultimate Butler" with API Integration!

Hello everyone! It's FullEle!

When you're customizing your own GPTs, you're bound to run into that mysterious item... yes, "Actions"!

"It looks kind of difficult..." "Schema? API? It just looks like a magic spell..."
If you've thought that and quietly pretended not to see it, please raise your hand honestly (lol). I was one of those people too!

But this "Actions" feature is actually a crazy magic button to evolve your GPTs from just a "knowledgeable AI" into...a "super-competent butler" that can actually "do work" by linking with external services!

This time, I'm going to explain the true nature and usage of this "Actions" feature, including all the results of my trial and error, more clearly than anywhere else!

First of all, what exactly is the "Actions" feature?

In a nutshell, the Actions feature isa mechanism to "connect" external APIs to GPT.

...even if I say that, it doesn't quite click, right? (lol).

This is like GPT-kun's"ability to call for delivery".

GPT-kun doesn't know information that isn't in his own kitchen (training data), such as "the latest weather" or "today's stock prices." In such cases, he uses a phone called the Actions feature to place an order with an external specialty restaurant (API), saying "Tell me today's weather!", and then tells us the information he obtained.

Doesn't that sound like a capable butler who can even handle meeting reservations and task creation?

[Preparation] What changes when you use the Actions feature?

Next, before we get into the specific settings, let's look at what changes on the GPTs settings screen when you add the "Actions" feature.

1. "Actions" is added under "Capabilities"!

An item called "Actions" will appear under the "Capabilities" section of the GPTs creation screen (where you choose things like web browsing or image generation).

From here, you can create new actions or manage the actions you've created.

2. The available models are limited to GPT-4o or GPT-4.1!

This is an unexpected pitfall, but it seems that when you enable Actions, the available models are limited to GPT-4o or GPT-4.1 (as of July 2025). If you want to use other models, it seems you'll need to turn off Actions.

3. You can also set it so that conversation data is not used for training!

By the way, from the "Additional settings" item, you can uncheck "Use conversation data in your GPT to improve our models." If you are handling important external information, it's safe to uncheck this!

[Diagram] A thorough dissection of the Actions settings screen!

You understand the theory, but you're probably wondering which part of the actual screen corresponds to what. Don't worry. Let's look at them one by one!

First is the "Schema" input field. You paste an "order form" written in a common rule called "OpenAPI Schema" here.

But you'd be troubled if you were suddenly told to write one, right? Rest assured! Convenient templates are provided.

These are the three convenient templates. The differences are like this!

Weather (JSON): This is a "practical example" that includes all the parameters, etc., assuming a weather forecast API. It is in JSON format.

Pet Store (YAML): This is a "reference book for advanced users" that contains various ordering methods (reading, updating, registering, deleting, etc.) as an API sample. It is in YAML format.

Empty template: This is a "blank sheet of paper" for those who want to write from scratch or those who want to copy and paste existing definitions.

For beginners, the royal road is to first look at the structure and try modifying "Weather" yourself!

Authentication: "Types of membership cards for the shop"

Next is "Authentication." This is the "ID card" required if the shop you are ordering delivery from is a "membership-only" shop.

Three options are displayed here too! The differences are as follows!

None (No Auth): This is exactlya "door without a lock". It is used for public APIs that anyone can access, and it is the easiest to try. However, since anyone can enter, be careful of misuse.

API Key: A method where everyone uses the same"shared master key". Implementation is simple, but it would be a big problem if this spare key leaked to the outside. My partner says, "Managing the key ring is the key" (Oh, did he think that was a clever pun? lol).

OAuth: "Name tag for each user + entry/exit record"This is the most secure method. It is used when accessing individual user data, such as writing to Google Calendar. However, the downside is that the settings are the most complex and difficult (lol).

It seems best to start by trying "None," choose "API Key" for limited access, and "OAuth" for full-scale service integration.

[Practical Guide] Let's actually integrate a weather forecast API!

I understand the theory. But you never really know until you try it yourself!
So, I actually tried out the GPTs Actions feature myself!

Step 1: Creating the Schema (How to write an order form)

First, in the settings screen, select "Weather (JSON)" from the "Examples" in the "Schema" section. That's it. Really, that's all there is to it (lol).

Then... look! Once you enter the schema correctly, "GetCurrentWeather" automatically appears below as an "Available Action"! This means GPT has recognized, "Oh, I can use this capability."

By the way, there are buttons for "Format" and "Test," but as far as I tried, they didn't work yet (lol). Looking forward to future updates!

Step 2: Setting up Authentication (Preparing your membership card)

Next is "Authentication." To explain again, this is like an "ID card" needed if the shop you're ordering delivery from is "members-only." Since this is an API anyone can use, we'll select "None."

Step 3: Save and start the conversation!

Now, that's all the setup! Save your GPTs settings and let's actually have a conversation!
This time, I equipped my original GPT, "Kansai-ben Assistant," with this weather forecast action.

Me: "Tell me the weather in Tokyo!"
AI: "Leave it to me! Just a sec..."

Whoa! It worked! It really fetched information from an external weather forecast site (simulated API) and answered in Kansai dialect!
Just by writing a schema, you can create an AI butler with original capabilities like this. It's truly moving...!

[Management] Editing and deleting created actions

Finally, here is how to manage the actions you've created.

If you look at the "Actions" section, you can see that the added action (in this case, weather.example.com) is registered.

By pressing the "Create new action" button, you can also give it multiple capabilities.

If you want to delete an action, press the trash can icon in the top right of the settings screen.

Then, a confirmation message saying "Are you sure you want to delete this?" will appear, so just press "OK" to complete the deletion!

Summary: Connect AI to the "outside world" and expand the possibilities!

How was it? Doesn't the Actions feature make you feel like you could build one yourself?

The Actions feature is the key that evolves GPT from a mere "chatting AI" into an "agent that properly interacts with the outside world".

I recommend starting with a simple API that doesn't require authentication, just like I did. That small step will surely be a big step toward creating your own ultimate AI butler!

Please enjoy integrating with AI!

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