Build your first agent from a message

The AI Agent Builder is a chat panel inside Agent Builder. You describe a job in your own words, and it adds the steps to the canvas, fills in their settings, connects them and gives the agent a name. You can keep talking to it to change the agent, or switch to editing the canvas yourself at any point.

Throughout this guide, John Martin builds an agent called Quote follow-up. Every Monday morning it finds BigChange quotes that have been open for more than 14 days and emails the list to Sarah Price, so she can chase them.

app.centrus.ai/app/agents/workflow-builder

Agents

Build modular AI workflows with reusable nodes

Quote follow-up6

1,240 / 10,000 creditsValidateResetSave draftSave and Publish

Monday 08:00

Weekly at 08:00 · Mon

Find open quotes

List quotes

Sent over 14 days ago

Keep ALL of 1 rule(s)

Collect quotes to chase

Collect into quotes

Write the follow-up list

GPT-5.6 Terra

Email Sarah the list

1 action enabled

5

AI Agent Builder

Edits apply live on the canvas

2

John Martin

Outlook. Sarah is sarah.price@meridianfm.co.uk

09:08

Centrus Agent Builder

I’ve built Quote follow-up. Every Monday at 08:00 it finds open BigChange quotes sent more than 14 days ago and emails Sarah the list.

• Say save and I’ll store it as a draft.
• Then connect BigChange on Find open quotes and Outlook on Email Sarah the list.

Applied 13 canvas changes.

09:09

3

Describe the workflow you want to build…

4

Minimise1

Map

2 warnings

1. 1AI builder opens the panel. While the panel is open, the button reads Minimise.
2. 2New conversation, Minimise and Close, in the panel's header.
3. 3The conversation. Your messages are on the right in navy, and the builder's replies are on the left.
4. 4The message box, where you type your request and attach files.
5. 5The agent it built, laid out and connected on the canvas.
6. 6The name it gave the agent. You can change it like any other name.

Whatever the builder does, you stay in control of the result. It never publishes an agent, never starts a run, and only saves a draft when you ask it to. You need edit access to the agent to use it. If someone has shared an agent with you as view only, the AI builder button is greyed out and reads You have view-only access to this agent when you point at it.

Start a new agent from Launch Builder on the Agents page, as Open Agent Builder explains, or open an agent you already have. There are two ways to open the panel:

Click AI builder again, now labelled Minimise, to hide the panel. Your conversation is kept, and it is all there when you open the panel again.

A new conversation opens with the line Describe the automation you need. I will add nodes and wire the canvas. Under it, Try an example lists three starting points. Clicking one puts its request in the message box without sending it, so you can change the wording first.

AI Agent Builder

Edits apply live on the canvas

1

Describe the automation you need. I will add nodes and wire the canvas.

Try an example

Daily reminder emailSchedule → Intelligence → Outlook

Receipt extractionImages → AI Extract → structured data

Daily industry newsSchedule → Web Search → summary email

2

3

Describe the workflow you want to build…

4

MinimiseMap

1. 1New conversation, Minimise and Close. Minimise and Close both hide the panel and keep the conversation. After the builder changes the canvas, Undo last AI canvas change appears in front of them.
2. 2Try an example. These only show in a new conversation.
3. 3The paperclip attaches a document, spreadsheet or screenshot. See Attach files and screenshots.
4. 4Send. Press Enter to send, or Shift and Enter to start a new line. The box grows to four lines as you type.

The panel always sits in the bottom right corner of the canvas, above the AI builder and Map buttons. It opens at 380 by 420 pixels. To make it bigger, drag its top edge, its left edge or its top left corner.

AI Agent Builder

Edits apply live on the canvas

John Martin

Every Monday at 08:00, find BigChange quotes sent more than 14 days ago that are still open, and email Sarah Price a list with the customer, quote reference, total and sent date.

09:07

Centrus Agent Builder

Two quick questions before I build this:

• Should the email go from your Outlook or your Gmail account?
• What is Sarah’s email address?

09:07

Describe the workflow you want to build…

MinimiseMap

1

2

3

1. 1The top edge makes the panel taller.
2. 2The left edge makes it wider.
3. 3The top left corner changes both at once.

• Smallest size: 300 pixels wide and 320 tall.
• Largest size: 720 pixels wide, or the width of the window less 32 pixels if that is smaller. The height can reach the window's height less 160 pixels, but never more than 85% of it.
• Remembered in this browser. The panel opens at the size you last left it, and shrinks to fit if you make the window smaller.

On a phone the builder shows the canvas without the Nodes and Details panels, and the AI Agent Builder takes up almost the whole width of the canvas. It works the same way, but you will find it easier to check the result on a computer.

09:41

Centrus

Agents

Build modular AI workflows with reusable nodes

Quote follow-up

Save and Publish

Monday 08:00

Weekly at 08:00 · Mon

Find open quotes

List quotes

Sent over 14 days ago

Keep ALL of 1 rule(s)

Collect quotes to chase

Collect into quotes

Write the follow-up list

GPT-5.6 Terra

Email Sarah the list

1 action enabled

AI Agent Builder

Edits apply live on the canvas

Centrus Agent Builder

I’ve built Quote follow-up. Every Monday at 08:00 it finds open BigChange quotes sent more than 14 days ago and emails Sarah the list.

• Say save and I’ll store it as a draft.
• Then connect BigChange on Find open quotes and Outlook on Email Sarah the list.

Applied 13 canvas changes.

09:09

Describe the workflow you want to build…

MinimiseMap

The builder does its best work when your first message answers three questions. You do not need to know which steps to use: describe the job the way you would explain it to a colleague.

AI Agent Builder

Edits apply live on the canvas

Describe the automation you need. I will add nodes and wire the canvas.

Try an example

Daily reminder emailSchedule → Intelligence → Outlook

Receipt extractionImages → AI Extract → structured data

Daily industry newsSchedule → Web Search → summary email

Every Monday at 08:00,1

find BigChange quotes sent more than 14 days ago that are still open,2

and email Sarah Price a list with the customer, quote reference, total and sent date.3

1. 1What starts it. A time, such as every Monday at 08:00, or an event, such as an email arriving or a job changing in your job system.
2. 2What it does. Where the information comes from and which records count. Use the words your team uses, such as open quotes or completed jobs.
3. 3Where the result goes. Who receives it, how, and what they should see.

A few more requests that give the builder enough to go on:

• When an email arrives in the reactive inbox with a photo attached, read the job number from the subject and add the photo to that job in BigChange.
• Every weekday at 17:00, list Simpro jobs completed today with no signed job sheet and email the list to the service manager.
• On the first of each month, add the previous month's invoiced totals from Xero to the Monthly figures workbook in Excel, on the Summary sheet.

Name real people, mailboxes, workbooks and sheets wherever you can. A request such as "send a report to the team" works, but the builder will either ask who the team is or leave the email step without recipients.

Before it builds anything, the builder asks about whatever it cannot safely guess: which email account to send from, who should receive the email, which Excel workbook and sheet to use, or what your job statuses are called. It asks up to three questions together, keeps them short, and builds once you answer.

AI Agent Builder

Edits apply live on the canvas

John Martin

Every Monday at 08:00, find BigChange quotes sent more than 14 days ago that are still open, and email Sarah Price a list with the customer, quote reference, total and sent date.

09:07

Centrus Agent Builder

Two quick questions before I build this:

• Should the email go from your Outlook or your Gmail account?
• What is Sarah’s email address?

09:07

1

Outlook. Sarah is sarah.price@meridianfm.co.uk

2

MinimiseMap

1. 1Its questions, all in one message.
2. 2Your answer. Reply in the same plain words. You can answer several questions in one line.

• If you already have a similar agent, the builder says so and asks whether to change that one or build a separate one.
• If the canvas is empty and the request is broad, it may offer to start from a close template and adapt it, rather than building every step from scratch.
• To skip the questions, add "just build it" or "use your best guess" to your message. It then builds straight away and leaves anything it did not know for you to fill in, which shows up as a warning in its reply. See Check what it built.

While the builder is answering, the panel shows a Thinking… card. Once it starts changing the canvas, a progress card takes its place, with a heading, a percentage and the step it is on.

AI Agent Builder

Edits apply live on the canvas

John Martin

Outlook. Sarah is sarah.price@meridianfm.co.uk

09:08

Thinking…

Describe the workflow you want to build…

While it works out what to do

AI Agent Builder

Edits apply live on the canvas

John Martin

Outlook. Sarah is sarah.price@meridianfm.co.uk

09:08

Creating workflow

58%

Applying 13 canvas operations…

Describe the workflow you want to build…

While it changes the canvas

The heading says what kind of work it is doing, such as Creating workflow, Investigating workflow, Validating workflow, Saving draft or Managing connections. The line under it changes as it goes, from Understanding your request… to messages such as Applying 13 canvas operations… and Checking workflow validation….

• Wait for the reply before sending another message. The Send button stays faded until the builder has finished.
• Leave the canvas alone while it works. If you move, add or change a step, the builder stops and shows AI update cancelled because the canvas changed. Send your message again when you are ready.
• Stay on the page. Minimising the panel is fine, but leaving or reloading the page stops the reply.

When a reply would change two or more things on the canvas, or replace it with a template or an earlier version, the builder shows Review canvas changes first. Nothing on the canvas changes until you choose. A reply that changes just one thing, such as a single setting, goes straight onto the canvas.

New Workflow Agent

1,240 / 10,000 creditsValidateSave draft

AI Agent Builder

Edits apply live on the canvas

John Martin

Outlook. Sarah is sarah.price@meridianfm.co.uk

09:08

Centrus Agent Builder

I’ve built Quote follow-up. Every Monday at 08:00 it finds open BigChange quotes sent more than 14 days ago and emails Sarah the list.

• Say save and I’ll store it as a draft.
• Then connect BigChange on Find open quotes and Outlook on Email Sarah the list.

Applied 13 canvas changes.

09:09

Describe the workflow you want to build…

MinimiseMap

Review canvas changes

The assistant wants to update your workflow. Review the summary below before applying.

What you will get

• Schedule: weekly at 08:00 on Mon
• AI step: Write the follow-up list
• Send email to sarah.price@meridianfm.co.uk (Email Sarah the list)

1

Planned changes

• Update workflow name or description
• Add trigger schedule
• Add integration bigchange_rest
• Add general filter
• Add general aggregate
• Add instructions global
• Add integration outlook
• Connect schedule → quotes
• Connect quotes → older
• Connect older → collect
• Connect collect → write
• Connect write → email
• Review and adjust canvas layout

2

Nodes added (6)

• schedule (trigger.schedule: Monday 08:00)
• quotes (integration.bigchange_rest: Find open quotes)
• older (general.filter: Sent over 14 days ago)
• collect (general.aggregate: Collect quotes to chase)
• write (instructions.global: Write the follow-up list)
• email (integration.outlook: Email Sarah the list)

3

Connections: 5 added, 0 removed.

Workflow name or description will be updated.

Keep current canvasApply to canvas

4

1. 1What you will get: the settings that matter most, such as when it runs, its AI steps and who it emails. Check names and addresses here.
2. 2Planned changes: every change in order, in the builder's own shorthand.
3. 3Nodes added: each new step's id, its type and the name it will show on the canvas.
4. 4Keep current canvas leaves the canvas as it was. Apply to canvas makes the changes.

If you click Keep current canvas, the builder's reply gets the note (Canvas changes were not applied.) and the canvas stays as it was. The reply still says how many changes it planned. Tell the builder what to do differently, and it plans again from the canvas as it is now.

When the changes go onto the canvas, the builder names the agent, lays the steps out, connects them and zooms the canvas to fit. It selects the AI step, so its settings open in the Details panel. Its reply sums up what the agent does and what is left for you, and ends with Applied 13 canvas changes.

Quote follow-up1

1,240 / 10,000 creditsValidateResetSave draft

Monday 08:00

Weekly at 08:00 · Mon

Find open quotes

List quotes

Sent over 14 days ago

Keep ALL of 1 rule(s)

Collect quotes to chase

Collect into quotes

Write the follow-up list

GPT-5.6 Terra

Email Sarah the list

1 action enabled

2

AI Agent Builder

Edits apply live on the canvas

5

Centrus Agent Builder

I’ve built Quote follow-up. Every Monday at 08:00 it finds open BigChange quotes sent more than 14 days ago and emails Sarah the list.

• Say save and I’ll store it as a draft.
• Then connect BigChange on Find open quotes and Outlook on Email Sarah the list.

Applied 13 canvas changes.

3

09:09

Describe the workflow you want to build…

MinimiseMap

2 warnings4

1. 1The name the builder gave the agent.
2. 2The steps. Click any of them to check its settings in the Details panel. Find your way round the canvas explains each part.
3. 3How many changes it made.
4. 4The status pill counts the problems still to fix. Here, the two warnings are the BigChange and Outlook accounts, which cannot be connected until the agent is saved.
5. 5Undo last AI canvas change puts the canvas back as it was before this reply.

Nothing is saved yet: the agent exists only on your screen until you save it, as the toolbar's Save draft button shows.

If the builder's own checks find a problem in what it built, its reply ends with a Validation line that counts the errors and warnings, followed by up to six of them. Click one to select the step it is about and move the canvas to it.

AI Agent Builder

Edits apply live on the canvas

John Martin

Every morning at 07:30, email the office team a summary of yesterday’s completed jobs. Just build it.

10:32

1

Centrus Agent Builder

I’ve built Daily completed jobs. I don’t know who is in the office team yet, so the email step has no recipients.

Applied 9 canvas changes.

Validation · 1 warning

Email the office team can send email but no default recipients are set: the agent will only send if its instructions specify who to email.

2

10:33

Describe the workflow you want to build…

1. 1A request sent with "just build it", so the builder did not stop to ask who the office team is.
2. 2The validation result. Errors are in red and warnings in amber. Click a line to go to that step.

If it shows more than six problems, a line such as +2 more issues follows. Click Validate in the toolbar to see the full list.

Keep talking to the builder to change the agent. Each message is read against the canvas as it is now, including any changes you have made by hand, so you can mix the two freely.

Monday 07:30

Weekly at 07:30 · Mon

3

Find open quotes

List quotes

Sent over 14 days ago

Keep ALL of 1 rule(s)

Collect quotes to chase

Collect into quotes

Write the follow-up list

GPT-5.6 Terra

Email Sarah the list

1 action enabled

AI Agent Builder

Edits apply live on the canvas

1

John Martin

Make it run at 07:30 instead.

09:14

Centrus Agent Builder

Done. Quote follow-up now runs every Monday at 07:30.

Applied 1 canvas change.

2

09:14

Describe the workflow you want to build…

MinimiseMap

1. 1Undo last AI canvas change.
2. 2One change, so it went straight onto the canvas without the review window.
3. 3The step it changed.

• Point at a step. Select a step on the canvas before you send, and the builder knows which one you mean, so "send this to Dylan Hughes as well" works.
• Ask about it. Questions such as "why did last Monday's run send nothing?" work too. The builder can read the agent's runs and its saved versions, and explain what happened before changing anything.
• Undo takes back one reply only. It restores the whole canvas to how it was before the builder's last change, which also removes anything you changed by hand since then. You then see Reverted the last AI canvas change.

Some changes are not allowed, because the step would not work that way. The builder then begins its reply with I tried to apply that change., explains which rule stopped it, and the panel adds A product rule blocked that change. The note above is what stopped it. Ask for a different approach, or contact support if the rule gets in the way of what you need.

A big request can take more work than one reply allows. The builder then stops with I stopped after 25 rounds before finishing this build., lists what it has already put on the canvas, and asks whether to carry on. Reply "yes" to continue from where it stopped.

Attach a document, spreadsheet or screenshot when it explains the job better than words: the rules your team follows, a sample report, or a picture of the list you want. Click the paperclip, or paste a file or screenshot straight into the message box. You can send a file on its own, without typing anything.

AI Agent Builder

Edits apply live on the canvas

Centrus Agent Builder

I’ve built Quote follow-up. Every Monday at 08:00 it finds open BigChange quotes sent more than 14 days ago and emails Sarah the list.

• Say save and I’ll store it as a draft.
• Then connect BigChange on Find open quotes and Outlook on Email Sarah the list.

Applied 13 canvas changes.

09:09

Quote chase rules.docx

Open quotes list.png

2

1

Only include quotes over £500, and use the wording in the document.

1. 1The paperclip opens your files. You can choose several at once.
2. 2Files waiting to be sent. Click the cross on one to remove it before you send.

• Pictures: JPG, PNG and WebP. The builder looks at the image itself, so a screenshot of a report or a form works well.
• Documents: PDF and Word (.docx).
• Spreadsheets: Excel (.xlsx and .xls) and CSV. The builder reads them as tables.
• Up to 5 files a message, each up to 20 MB.

Older Word files (.doc) can be attached, but the builder cannot read what is in them, so save them as .docx first. If a file is the wrong type you see "Quote list.pages" is not a supported file type., with the file's own name, and adding a sixth file shows You can attach up to 5 files per message.

The builder saves only when you ask. Reply "save the draft", or click Save draft in the toolbar yourself: both do the same thing. The first time a new agent is saved, Centrus shows Draft saved. You can now connect integrations and test run it.

Quote follow-up

1,240 / 10,000 creditsDraft savedRunsSettingsSave and Publish

Monday 08:00

Weekly at 08:00 · Mon

Find open quotes

List quotes

Sent over 14 days ago

Keep ALL of 1 rule(s)

Collect quotes to chase

Collect into quotes

Write the follow-up list

GPT-5.6 Terra

Email Sarah the list

1 action enabled

AI Agent Builder

Edits apply live on the canvas

John Martin

Save the draft.

09:11

Centrus Agent Builder

Saved Quote follow-up as a draft. Now connect your accounts:

• BigChange on Find open quotes
• Outlook on Email Sarah the list

09:11

1

Describe the workflow you want to build…

MinimiseMap

Draft saved. You can now connect integrations and test run it.

1. 1The builder's reply lists the steps that need an account.
2. 2Connect, in the step's Details panel. Choose the account to use.

Accounts can only be connected once the agent is saved. Save before connecting, because connecting takes you to the account's sign-in page and then reloads the agent as it was last saved, so anything unsaved is lost. If you need a second account, such as another Outlook mailbox, ask the builder and it replies with a link to connect it.

The builder can also change who can use or edit the agent, if you are its owner or an admin. It asks you to confirm with "yes" first, and the change takes effect straight away, without saving. Share an agent covers access in full.

Each agent keeps its own conversation with you. When you open the agent again, on this computer or another, the panel picks up your latest conversation where you left it. Conversations are private: a colleague who opens the same agent sees their own conversation, not yours.

AI Agent Builder

Edits apply live on the canvas

3

1

Conversation compacted

2

John Martin

Add the quote owner to each line of the list.

14:20

Centrus Agent Builder

Done. Each line now shows who owns the quote.

Applied 1 canvas change.

14:21

Describe the workflow you want to build…

1. 1How full the conversation is. The bar fills as the conversation grows.
2. 2Conversation compacted. In a long conversation, the builder condenses the earlier part of the chat so it can keep going.
3. 3New conversation clears the chat and starts again. The canvas is not affected.

A conversation on a new agent that has never been saved moves across to the agent when you first save it. Start a new conversation when you move on to a different change, so the builder is not working from old instructions.

Some decisions always stay with you, and a few limits apply to every conversation.

• Publishing and running stay with you. When the agent is ready, test it as Test an agent before it goes live explains, then publish it from the toolbar.
• Passwords never go in the chat. If a step needs to sign in to a website, the builder asks you to enter the login in that step's Credentials section instead.
• It warns before replacing a live agent. If a change would replace the steps of a published agent, it checks with you first.

Each reply uses automation credits from your organisation's monthly allowance, based on the AI work behind it. A short answer uses very little; a first build that adds and checks many steps uses more. The credits counter in the toolbar includes them, and so does the Builder Chat column of the Agent Builder Usage report. Chats on an agent that was never saved are listed under Unassigned. See Automation credits and usage limits and Credits.

• Find your way round the canvas: check and change each step the builder added.
• Test an agent before it goes live: try the agent on real data without sending anything.
• Publish, pause and restore versions: put it live, and go back to an earlier version if you need to.
• Build and edit agents from chat and WhatsApp: draft an agent from an ordinary chat instead of the builder.
• Automation credits and usage limits: what building and running agents uses, and where to see it.