So let me clarify and say everything is Power Automate, but bare with my explanation.
Scenario 1: You create what I call an "internal" Tool to Copilot. This means that you specifically say Add a Tool, then you pick something like Send an Email. And you populate its inputs directly from within the Copilot and it shows up on the Activities Tab.
Technically you can Edit this in Flow, but since its a single "action" there is no real need.
Scenario 2: You add a Trigger (bare with me), where Triggers ARE power automate automated Flows, things like when an Email Arrives.
What happens is you tell it to add a Trigger, pick your "action" and save. On the right side of the Trigger name, you can click ... and pick Open in power Automate and do more work to it, as it opens a window to power automate.
Scenario 3: In a Topic, you pick Advanced, Add a Tool. Now, here you have 3 options
a) Select Create a new Tool
b) Select an existing Tool
c) Its another variation of 1 or 3
If you do a) then it will kick you into power automate to add whatever code you want, UNLESS you only pick an "internal" flow.
b) if you select an existing tool, you can search for existing Flows and then you can also say open in power automate to edit.
So if you share your screen pictures, I can tell you which one you are doing and can help you.
BTW. You can actually just GO to powerautomate.com, then log in, select the environment with your Agent, then Flows (my Flows)
it will list ALL the "Tools" you created for your Copilot and you can edit them there :-) directly.
i do that one all the time.
The Copilot doesn't care you did it and it works immediately after you publish the Flow Inside the Flow Edit Screen
If these suggestions help resolve your issue, Please consider Marking the answer as such and also maybe a like.
Thank you!
Sincerely, Michael Gernaey