cant connect agent to a DB action and to MCP server in Microsoft Copilot Studio

Question

I have 2 problems:

1. I can’t connect my agent “MCP Agent Test” to any database, I tried to connect it to a Postgres DB and to a MySQL DB. When connecting to Postgres, I get the error:

“Test connection failed. Details: Credentials are missing or not valid. inner exception: The credentials provided for the PostgreSQL source are invalid. “

I can assure you the credentials are correct, I succeeded in connecting to the database from my computer (DBeaver), the credentials are correct, it’s publicly accessible, and there is no firewall.

So I tried to connect to another MySQL database, but it required a transit gateway - why do I need another resource to connect to a MySQL database? Is there an easier way to do this? Or can you please guide me on how to create the transit gateway correctly?

I even tried creating and connecting to “Azure Database for MySQL” - but I can’t even edit the existing faulty connection, it looks like a bug in the UI - please help me edit the connection and fix it, or create a new one

I specifically need the Postgres connection to work, please help me understand what is going on with the credentials.

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2. I can’t connect the agent to my MCP server, and there is no error or documentation regarding what to do. I followed your docs:

https://learn.microsoft.com/en-us/microsoft-copilot-studio/agent-extend-action-mcp

But it doesn’t work.

I created an “MCP Test” custom connection in Power Apps, it seemed to work - There are no errors, so I assume the connection is OK.

I connected the agent to the MCP server action using a “Custom Connector”, it says that the agent has connected to it successfully. I published the agent, but after prompting it with my request, it gets stuck, without an error, and there is no way for me to debug it.

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I couldn’t find any info about both of these problems online, I request your help since I can’t continue my work.

Thank you.