Mastodon

Mastodon channels post through the UmbHost.Automate.Mastodon package and its Create Mastodon Status action (mastodon.createStatus). It works with any Mastodon instance.

dotnet add package UmbHost.Automate.Mastodon

What Mastodon needs

An access token for an application on the account’s instance.

1. On the instance, open Preferences → Development → New application, with the scopes write:statuses and write:media. Copy the access token.

2. Put it in configuration:

   { "Umbraco": { "Automate": { "Secrets": { "MastodonAccessToken": "..." } } } }

   As an environment variable: Umbraco__Automate__Secrets__MastodonAccessToken.

The Automate connection

Automate → Connections → Create → Mastodon. Enter the instance URL, for example https://mastodon.social. Validate checks the token.

Then add the channel as described in Connecting networks.

Channel options

Option	Values	Default
visibility	public, unlisted, private or direct	public

The visibility applies to every post on the channel. Changing it updates the channel’s automation.

What is sent

Post field	Sent as
Text	The status text. The link, if any, is added at the end of the text.
Image	Optional. A JPEG, PNG, GIF or WebP. The action waits for the instance to process it.
Image alt text	Sent.
Link title and description	Not sent.

Social counts 500 characters, with each link counting as 23, as most instances do. An instance with a different limit isn’t known to Social. See Network limits.

When a post fails

The status request carries an idempotency key that Mastodon honours for an hour, so a retried request inside the action returns the original status rather than posting twice.