Frequently asked questions

Channel registration

Can I register a new Channel without an endpoint URL?

Yes. It is possible for your Channel to be registered and approved without an endpoint URL. You can add an endpoint URL at any time. However, your Channel will not be able to receive any requests without an endpoint URL. You will also receive a notice reminding you to add an endpoint URL.

Is a contact mailing list address required?

Yes. You must provide a contact mailing list email address. This email address allows us to contact you with important information regarding the LINE platform.

Are second and third contact mailing list addresses required?

No. They are not required.

User information

Is it possible for a user’s MID to change?

No. A user’s MID is never changed unless the user deletes the account. If the user creates a new account, a new MID is issued.

Can I use the Friend List API?

No. The Friend List API is not provided.

Can I get a count of how many friends my official account has?

Yes. You can see the number of friends your official account has on the management page for your official account provided by LINE. You cannot retrieve the count with an API.

Can I get a list of the users who have blocked my official account?

Yes. You will receive a opType: 8 operation, when a user blocks your account.

Can I send messages to users who have blocked or deleted my official account?

No. If you try to send a message to users who have blocked or deleted your official account, the API will respond successfully but your message will not be sent. You will not be charged for messages that are not sent.

What information must be deleted when a user blocks my official account?

All user information (MID, nickname, icon image and status message) retrieved by APIs and all messages (including multimedia files) sent by the user must be deleted.

Receiving operations and messages

What is the maximum length of messages that users can send?

10,000 characters.

In what situation does the LINE server send multiple messages in one request to my Business Connect server? What is the format for such requests?

When many users send messages to your official account in a short period of time, the LINE server will send multiple messages (up to 100) as one request to your Business Connect server . The request will look like this:

{"result":[{1st event},{2nd event},...]}

Calling APIs

How many users can be specified in the to property value in one request?

A maximum of 150 users can be specified in one request. You will be charged based on the number of users you send messages to.

Do image, audio, and video content, which I want to send to users, have to be stored in my Business Connect server?

Yes. the LINE app retrieves image, audio, and video content directly from your Business Connect server.

When an access token is updated, is the old access token invalidated?

Yes. When the access token is updated by calling API, the old access token will be invalidated. Make sure that errors do not occur while the access token is updated (for example, temporary stoppage of message transmission).

What is the maximum size of the request body when sending messages?

For “POST /v1/events” requests, the size of the request body must be less than 8192 bytes.

Communication between servers

How long does it take to send and receive messages?

It depends on the load on the LINE platform and your Business Connect server.

Can I send many requests to the LINE platform for load testing?

No. You cannot send many requests to the LINE platform for load testing.

Can I get a virtual user account for testing?

No. We do not issue virtual user accounts for testing.