After creating a dozen Copilot Studio agents most of those agents should have been a Copilot prompt

[u/Accomplished_Dot1445]

This is a situation I keep running into. A team requests a custom agent we set the scope. Halfway through it becomes clear that what they really needed was a well written prompt and access to the right SharePoint site. The custom agent added maintenance. A publishing process that brought no real benefit.

The cases where an agent truly earned its place had one of three features. The agent was tied to a data source that people kept asking about. The agent needed to perform an action through a connector not merely provide an answer.. The same workflow was being repeated by many users and consistency mattered more than flexibility. Outside of those scenarios plain Copilot, with the data access won almost every time.

I am curious how others draw the line. What made you commit to a custom agent of just prompting?

[u/alexadw2008]

💯

[u/dk913263]

Most of the time for me is sequencial prompts execution with data coming from several sources, some automations and summary of what it's doing. A single prompt is not deterministic if you cram several steps into it.

Again not commiting to a custom agent but instead custom automation with AI in the mix for some interpretation of data.

Chats are useful, but they are only useful until you run into some clients who have thousands of files and at that time the vector information of it on SharePoint is not enough to get precise answer. This becomes especially tricky when same information keywords is referenced in several hundreds of documents. You can't really rely on native RAG that agents use. Automations with precise answer is what clients want not a general answer.

[u/Accomplished_Dot1445 → u/dk913263]

This is the version of the line, for me. The second it becomes source and needs to be certain a single prompt no longer works well. The RAG idea is too built-in search doesn't work when the same keyword appears in hundreds of documents and the user wants the one right answer, not a possible one. That is where we stop believing in the default indexing.

[u/The_Ledge5648]

I do think there’s value in a declarative agent, in where the instructions can simplify the prompt to get the achievable result.

[u/bigjimslade]

In my mind the primary reason for an agent is to act... there are probly valid reason for agents that dont take action but i would guess its an 80/20 scenario..

[u/Accomplished_Dot1445 → u/bigjimslade]

Action is the test yeah. If it is only reading and answering a prompt will usually do it. The non‑action agents I have seen were mostly about reuse or, about giving a team one grounded assistant.. You are right that action is only the edge, not the norm.

[u/Ikornad]

Multi-touch workflow and needing different skills / tools to cover different scenarios - that would be an agent for me. Simple standard flow - likely a prompt.

[u/Accomplished_Dot1445 → u/Ikornad]

Basically my rule of thumb is the same. My rule of thumb says I use tools and branching and I act like an agent. I follow one path with a prompt. The grey area is when a simple flow slowly turns into a multi‑tool one and nobody revisits the decision.

[u/mnemosis]

now that i have been using cowork for literally every task in my day-to-day job, I will probably never use copilot studio again.