OAuth2 fails for Mastodoncommunity node

[xut]

Describe the problem/error/question

I use the n8n community node to connect to Mastodon. But the OAuth2 connection fails.

What is the error message (if any)?

I get the error “The requested scope is invalid, unknown, or malformed.”
But the scope I gave Mastgodon is just “write”.

But this is the scope I checked in the Mastodon backend:

I also tried with just “read” (after checking this in the Mastodon backend) and “write:statuses” (which would be enough) - both fail with the same error message.

Information on your n8n setup

• n8n version: 1.101.2
• Database (default: SQLite): SQLite
• n8n EXECUTIONS_PROCESS setting (default: own, main): own
• Running n8n via (Docker, npm, n8n cloud, desktop app): Docker
• Operating system: Ubuntu 24.04.2 LTS

[Jayraj_Chhaya]

@xut

I also tried with just “read” (after checking this in the Mastodon backend) and “write:statuses” (which would be enough) - both fail with the same error message.

The error usually happens because Mastodon expects specific scope names, and they must match exactly what the instance allows. Common valid scopes are:

• read

• write

• follow

• write:statuses

If you’re getting “invalid scope,” it often means:

1. The scope string is case-sensitive or formatted incorrectly (no extra spaces or commas).

2. The Mastodon instance you’re connecting to does not support that scope for third-party apps.

3. Some community nodes in n8n expect comma-separated multiple scopes, while Mastodon expects space-separated scopes in OAuth2.

Fix:

• Use the exact scope string shown in Mastodon when registering the app.

• For posting statuses, try write:statuses exactly as shown.

• Make sure multiple scopes are space-separated, e.g., read write:statuses.

[krisn0x]

Can you try without the scopes and also try changing Authorization to Body, again with and without scopes? Make sure to list all scopes the app has, separated by space.