Agent Builder (Copilot Studio Lite): Creating a Copilot agent step by step (2026)
This article was written on November 7, 2026, based on the Microsoft Learn documentation for Agent Builder (overview, creation, knowledge sources, sharing, licenses), which was consulted that day. The French interface of Microsoft 365 Copilot frequently changes its terminology: rely on the logical sequence of steps rather than the exact wording. The Microsoft Ignite conference, from November 17 to 20, 2026, will likely introduce new features that we will incorporate.
Agent Builder is the tool integrated into Microsoft 365 Copilot that allows any employee to create an AI agent in minutes by describing their requirements: a specialized assistant that follows set instructions and responds using selected documents. Microsoft also calls it Copilot Studio Lite, as it's a simplified version of Copilot Studio. This guide explains what Agent Builder is, where to find it, what your license allows you to do, how to create your first agent in seven steps, how to share it, its limitations, and when to upgrade to Copilot Studio. It also provides the NextStart Agent Instruction Framework, which must be completed before opening the tool.
The essentials in five lines
- Agent Builder, also called Copilot Studio lite, is used to create agents in Microsoft 365 Copilot, on the web and in Teams, without code or administrator rights.
- An Agent Builder agent consists of a name, a description, instructions (maximum 8,000 characters), knowledge sources, and starter questions.
- What he can read depends on the license: the web and your instructions with Copilot Chat, SharePoint and your files with pay-as-you-go billing, your emails and your Teams meetings with the Microsoft 365 Copilot license.
- He doesn't know how to act In other applications: to create a ticket or launch a flow, you need to copy the agent into Copilot Studio.
- The NextStart Agent Instruction Frame structure the instructions into five blocks: role, task, sources, rules and response format.
Agent Builder: definition
Agent Builder is the agent creation workshop integrated into Microsoft 365 Copilot. It produces what Microsoft calls... reporting agents Specialized versions of Copilot, to which a role, instructions, and sources are "declared" without any programming. The agent uses the same engine as Copilot, but it retains its instructions from one conversation to another and can be shared.
The name has changed several times. The tool first appeared in October 2024 as "Copilot Studio agent builder," then Microsoft presented it as the "lite" version of Copilot Studio. Microsoft Learn documentation now calls it "Agent Builder in Microsoft 365 Copilot," and Microsoft's pricing page refers to it as "Copilot Studio Lite." All three names refer to the same tool. To see where Agent Builder fits within the full suite of tools, see our article. Copilot Studio: what is it?.
Microsoft cites two typical uses: an agent who coaches writing or presentations according to the organization's standards, and an onboarding agent who answers a new employee's questions about their team. The rule is the same for everyone: one agent per repetitive task, using reliable sources.
Where can I find Agent Builder?
Agent Builder opens from the Microsoft Copilot app, using your work account: on the web at microsoft365.com/chat or office.com/chat, and in Teams, desktop or web version. In the left pane, choose New agent (New agent). The tool is not available on mobile applications. It is available in both tabs of Copilot, work and web.
If you don't see "New agent," there are three possible reasons: your administrator has disabled Agent Builder for your organization or group, your license doesn't allow agent creation, or your company network is blocking the *.api.powerplatform.com domain, which Agent Builder requires. The first two can be resolved in the Microsoft 365 admin center, and the third in your firewall or proxy settings.
What your license allows you to do with Agent Builder
This is the question that determines everything else: an agent can only read the sources that its user's license allows. Microsoft distinguishes three situations.
| Situation | What the agent can use | Cost |
|---|---|---|
| Copilot Chat, without pay-per-use fees | Instructions, general or limited web searches, data analysis and creation of documents or graphs using code, image creation | Included in the Microsoft 365 subscription |
| Copilot Chat with pay-as-you-go pricing activated by the administrator | In addition: SharePoint, OneDrive, files uploaded to the agent, Copilot connectors, Dataverse | Usage in Copilot Credits, billed via Copilot Studio |
| Microsoft 365 Copilot license (the " Copilot Premium ") | In addition: the user's emails, people, conversations, and Teams meetings | Included in the license |
Two points are important in practice. First, pay-per-use is disabled by default for Copilot Chat users: without administrator action, an agent connected to SharePoint will not work for them. Second, the rule applies to the person using the agent, not just the person creating it: if you share an agent relying on your emails with a colleague without a license, they will get an error. Furthermore, Microsoft sources differ on the creation of agents without a license or pay-per-use: check the behavior in your tenant. Details of the two offers are in Copilot Chat or Microsoft 365 Copilot: what are the differences? and Copilot Chat Kit.
Create an agent with Agent Builder in seven steps
The example shown here is a "Tender References" agent for a sales team: it retrieves customer references and template paragraphs relevant to a new tender in SharePoint. Allow one hour for a first usable version.
1. Prepare the agent before opening the tool
Write a one-sentence summary of the agent's mission, list their future users, gather their resources, and note ten real-life questions they will ask. For example: "Find the references and sample paragraphs useful for a request for proposals," for the six sales representatives on the team, using the SharePoint library "Customer References" and the folder "Technical Reports." These ten questions will serve as a test in step 6.
2. Open Agent Builder and choose your method
In Microsoft Copilot, choose New agentThree paths are available: describe the agent in natural language in the description tab, and Agent Builder configures it for you (the method recommended by Microsoft); start from a model pre-configured; or proceed directly to manual configuration ("Skip to configure"). For a first agent, describe it in natural language, then manually follow the generated instructions.
3. Fill in the name, description, and instructions
In the tab Configurator ("Configure"), the name It must be no more than 30 characters. DescriptionThe description, up to 1,000 characters, serves two purposes: it is displayed to users and it helps Copilot know when to call the agent; keep it short and precise. instructionsUp to 8,000 characters are the core of the agent. Use the template below.
| NextStart Agent Instruction Frame Block | What is written there | Example: "Tender References" |
|---|---|---|
| 1. Role | Who is the agent and who does he work for? | "You are the assistant to the sales representatives on the Key Accounts team for the preparation of tenders." |
| 2. Task | What he does, step by step | "Based on the summary of a call for tenders, you propose the three closest client references and the standard paragraphs to be used." |
| 3. sources | Where he looks, and what he does when he doesn't find it | "You rely solely on the documents provided. If no reference matches, you say so and you don't invent anything." |
| 4. Rules | What he must refuse are the precautions | "You never mention a contract amount. You only report any reference older than three years." |
| 5. Format | The form of the response | "A table: client, year, subject, why it's relevant, link to the document. Then the sample paragraphs, each with its source." |
Block 3 is the one most often overlooked, and it's what prevents made-up answers. For a more complete method, with another example of fully written instructions, see Creating an AI agent in a company: the 7-step method.
4. Add the sources of knowledge
In the Knowledge section, add sources by their address or by browsing them. Each type of source has a limit per agent:
| Source | Limit per agent |
|---|---|
| Public websites | 4 addresses |
| SharePoint files, folders, or sites | 100 fichiers |
| SharePoint Lists | 1 list (20,000 lines and 50 MB of text maximum) |
| OneDrive files | 50 fichiers |
| Teams conversations and meetings | 5 conversations and 5 meetings |
| Files uploaded from your computer | 20 files (Word, PDF and PowerPoint up to 512 MB, Excel up to 30 MB) |
| Copilot connectors, Dynamics 365 data, and Power Apps | No encrypted limit, activation by administrator |
Three simple steps can prevent many disappointments. Prefer short, up-to-date documents to an entire SharePoint site. For an Excel file, keep the data on a single sheet: the agent responds better that way. And be aware that adding a SharePoint site doesn't automatically add its lists; you have to select the list itself.
5. Adjust the capabilities and response mode
Two capabilities are available: the code interpreter, which analyzes data and produces documents or graphs, and the image generator. You can also add... skills to the agent, either by providing a skill package or by describing it in natural language. Finally, the Model section sets the default response mode: automatic, quick response, or in-depth reflection. The user can always change this. For a document search agent like our example, the automatic mode is sufficient.
6. Test in the Try tab
The tab Try ("Try it") activates as soon as the agent has a name, a description, and instructions. Ask it your ten real questions and note each answer: correct, incomplete, false, or made up. Correct the instructions or the source code, then run through the entire game again, as one correction can break another. The image generator does not work in this test environment: check it after creation. Finally, add three or four starter questionswhich will show users what the agent can do.
7. Create and share the agent
Choose Create The agent is initially private. The button Share A window opens with two roles: "Can edit," for co-owners who can edit and manage the agent, and "Can discuss," for those who only use it. A group can only have the "Can discuss" role. The same window provides a link to copy into a message and, if the administrator allows it, a sharing toggle for the entire organization: the agent then appears in the Copilot Agent Store. To have it listed among the agents created by your organization, submit it to the organization's catalog: an administrator approves it in the Microsoft 365 admin center.
When sharing, Agent Builder can automatically share the SharePoint files and folders you've added, provided you have the necessary permissions. It never grants access to an entire site. In all cases, the agent respects each user's rights and privacy settings: it only shares what the individual is authorized to see.
Modify, manage and delete an agent
Your agents can be found in the left-hand panel of Copilot, under "All agents," or via "New agent," then "View all agents." Any owner can edit the agent, either using natural language or in the Configure tab. Changes are saved automatically but only become visible after you select them. Update profileThese updates may take a few minutes to reach users. If the agent relies on SharePoint files, re-share it after the update. The deletion is permanent for all owners and users.
Agent Builder or Copilot Studio: when to switch tools?
| Your need | Agent Builder | Copilot Studio |
|---|---|---|
| Respond using documents and the web | Yes | Yes |
| Act in another tool: ticket, list, send, approval | No | Yes, via connectors, streams, and MCP servers |
| To trigger itself, via an email or a file | No | Yes |
| Can be used in a group or one-on-one Teams conversation | No | Yes |
| To be published on a website or other channel | No | Yes |
| To be finely managed: environments, data protection rules, analytics | Microsoft 365 admin center | Power Platform admin center |
| Can be created by any employee in ten minutes | Yes | Rather by trained creators |
Switching from one to the other doesn't mean starting from scratch: Agent Builder offers to copy the agent into Copilot Studiowhere actions, connectors, and flows are then added. The best practice is therefore to start with Agent Builder, run the agent for a few weeks, and then copy it to Copilot Studio when the need for action arises. The step-by-step instructions for Copilot Studio are in our guide. Copilot Studio: Create your first agent step by step.
Limitations and common errors
- No agents in Teams conversations. Agent Builder agents are not used in Teams group or one-on-one conversations, only in Copilot.
- SharePoint may be blocked. If the organization has enabled restricted SharePoint search, SharePoint cannot be used as a source. And if the administrator has disabled web search in Copilot, the web is blocked even if the agent switch remains displayed.
- Some confidentiality labels cause the agent to fail. A file that is encrypted with two keys, has user-defined permissions, or is password-protected is not being used as a source, sometimes without an error message. Remove these files.
- Sharing an agent does not share a site. Only added files and folders are shared automatically. A user without rights to a document will never see its contents in replies.
- Wanting an agent who does everything. One agent per task, with a scope written in his instructions, gives reliable answers; an agent "assistant of the service" with ten missions gives none.
- Do not test with real questions. The questions invented by the creator always get through; those of future users reveal the gaps.
For agent ideas categorized by profession, see our page AI agents and assistants by professionAnd to help your teams build their first agent on a real-world task, with support, our workshop Agent Party® takes place in Agent Builder, in your tenant, in one hour or half a day.
F.A.Q
What is Agent Builder, in one sentence?
Agent Builder is the Microsoft 365 Copilot tool that allows you to create an AI agent without coding, i.e. a specialized version of Copilot with its own instructions and its own sources, and then share it with your colleagues.
Are Agent Builder and Copilot Studio Lite the same thing?
Yes. The tool was initially called "Copilot Studio agent builder," then Microsoft introduced it as the lite experience of Copilot Studio. Microsoft Learn now calls it "Agent Builder in Microsoft 365 Copilot." All three names refer to the same tool.
Is Agent Builder free?
Agents who rely on instructions and the web are included in Copilot Chat. Those who read SharePoint, OneDrive, or files consume Copilot Credits for unlicensed users, if the administrator has enabled pay-as-you-go pricing. With a Microsoft 365 Copilot license, everything is included.
Why can't I see Agent Builder in Copilot?
Either you are on a mobile device, where the tool is unavailable; or the administrator has disabled it or only made it accessible to certain groups; or your license does not allow the creation of agents; or the network is blocking the *.api.powerplatform.com domain. Contact your IT department.
How many documents can be given to an agent?
Up to 100 SharePoint files, 50 OneDrive files, 20 files uploaded from the computer, one SharePoint list, and four websites per agent. Instructions are limited to 8,000 characters.
How do I share an agent with the entire company?
In the Share window, enable sharing to the entire organization if the administrator allows it: the agent will then be visible in the Agent Store. To have it presented as an official agent of the organization, submit it to the catalog: an administrator will approve it before deployment.
Can an Agent Builder agent send emails or create tickets?
No. Agent Builder does not allow you to create actions that interact with other services. To make an agent work, copy it into Copilot Studio and add connectors or flows to it.
Sources
- Microsoft Learn, Agent Builder overview, accessed November 7, 2026.
- Microsoft Learn, Build agents in Agent Builder, accessed November 7, 2026.
- Microsoft Learn, Add knowledge sources to an agent in Agent Builder, accessed November 7, 2026.
- Microsoft Learn, Share and manage agents built in Agent Builder, accessed November 7, 2026.
- Microsoft Learn, Agent capabilities and licensing models, accessed November 7, 2026.
- Microsoft Learn, Licensing plan and cost for Microsoft 365 Copilot extensibility, accessed November 7, 2026.
- Microsoft Learn, Agents admin guide for Microsoft 365, accessed November 7, 2026.