Microsoft Word in Agent Builder

The Microsoft Word step lets an agent create and update Word documents in a Microsoft 365 OneDrive as part of a run. It can find a document by name or create it, list the .docx files on that account, read a file's name and link, append headings, paragraphs, lists, tables and images, format matching text, replace a phrase, save the file, or download it as a Word document or a PDF. Each step does one thing, picked from 8 actions, and hands what Microsoft sends back to the next step. A download hands on the file, so a later Outlook step can attach it to an email, or a File Parser step can read it.

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Job letter after a visit

1,240 / 10,000 creditsValidateResetRunsSettingsUpdate & Publish

Job finished

Job status changed

Fetch the job

Get job

Write the letter

GPT-5.6 Terra

Write the document

Insert blocks · Job letter, Riverside House

2

AI builderMap

1. 1Microsoft Word in the Integration group of the Nodes panel.
2. 2The step on the canvas. Its summary shows the action and the document title, Insert blocks · Job letter, Riverside House.
3. 3Connection: the Microsoft account this agent uses. With more than one account, Account picks which one this step uses.
4. 4Actions: the one action this step performs. Insert blocks is selected.
5. 5Document title: the file name in OneDrive, without .docx.

Centrus works alongside Word. The file stays in the OneDrive of the account you sign in, as a real .docx, and anyone who can open that OneDrive can open it in Word. The step does not replace the job system. To ask for a document in a conversation rather than in an agent, see Microsoft Word in chat. How connections differ across chat, Agent Builder and Train is in Integrations overview.

Open the agent in Agent Builder and find Microsoft Word in the Integration group of the Nodes panel, under Microsoft Excel and above Google Sheets. Drag it onto the canvas and connect the step before it to its left-hand side. A new step already has Insert blocks chosen, so its summary reads Insert blocks. Once you type a Document title, the summary becomes Insert blocks followed by that title. If you clear the action, the summary reads No actions selected.

Job finished

Job status changed

Microsoft Word

Insert blocks

2

1. 1Microsoft Word in the Integration group. Drag it onto the canvas.
2. 2The new step. It already reads Insert blocks, which is the action a new step starts with.

On a phone, Agent Builder shows the canvas only. The Nodes panel is hidden on screens narrower than 768 pixels and the Details panel on screens narrower than 1,024 pixels, so you can follow an agent's steps on a phone but need a tablet or computer to add a Word step or change its settings.

09:41

Centrus

Agents

Build modular AI workflows with reusable nodes

Chase overdue invoices

Save and Publish

Job finished

Job status changed

Fetch the job

Get job

Write the letter

GPT-5.6 Terra

Write the document

Insert blocks · Job letter, Riverside House

The Word connection belongs to this agent alone. It is separate from the Microsoft Word card on the Integrations page, so connecting chat does not connect the agent, and connecting the agent does not connect chat. One connection covers every Word step on the agent, so you only sign in once per agent. An agent can hold more than one Microsoft account. Each Word step then picks which one to use.

You sign in with Microsoft. There is no customer ID or secret to copy. The person who signs in needs a work or school account whose OneDrive should hold the documents, such as accounts@meridianfm.co.uk. Centrus asks Microsoft for permission to stay signed in, to read and write all files that account can open, and to read the signed-in profile. That file permission is wider than Word: it covers every file the account can open, not only .docx documents. Microsoft's page asks you to pick an account.

1. 1Save the agent with Save draft. Until it has been saved once, the Connection section reads Save this workflow as a draft first, then connect the account. and Connect is greyed out.
2. 2Select the Word step. In the Details panel, open Connection and click Connect.
3. 3Centrus leaves Agent Builder and opens Microsoft's account page. Choose the account, then accept the permissions. You have 10 minutes to finish. After that the sign-in expires and you start again from Connect.
4. 4You return to the agent. A notice reads Microsoft Word connected for this agent, and Connection reads Connected, followed by that account's address.

Centrus does not store a password. Microsoft accepts or refuses the sign-in. If you close Microsoft's page before you finish, nothing is saved and Connection stays Not connected. If Centrus cannot open Microsoft at all, you see Failed to start Microsoft Word connection. Try Connect again. If the sign-in fails after you have left the builder, you land on the agents list and the page does not say why. Open the agent and click Connect again.

Several accounts. After the first account is connected, open Settings in the toolbar. Under Integrations, Add another account starts a second Microsoft sign-in and leaves the first account in place. Each row can be renamed, made primary, or disconnected on its own. On the step, Account appears once the agent has two or more accounts, or if the step still points at an account that has been disconnected. Primary account (default) follows whichever row is marked primary in Settings. A named row, such as john.martin@meridianfm.co.uk, locks this step to that account. The list on the step shows the primary row with (primary) after the address.

Whose account a run uses. Integration mode, in Settings, is shown to the agent's owner and to an organisation administrator. Agent-level is the default, and it is the mode Word uses. Every Word step uses the account connected on the agent, whoever starts the run. Per-user is only offered when the agent starts from chat, and the note under the switch talks about Outlook and Gmail. Word is not included. If the agent is switched to Per-user, the Word step still uses the agent's own account. Its Connection section says so: the step always uses the agent's connection, because Word has no per-user credentials. The Account list stays available. Keep an agent that writes documents on Agent-level so the Settings note and the step agree. For how sharing and this switch fit together, see Share an agent.

Sharing and copying the agent. When you share an agent, its Word connection stays on the agent. People you share it with cannot see or copy the sign-in, and their runs write to the agent's OneDrive. When you duplicate an agent, the steps are copied and the connection is not. The copy says to connect again. There is no Copy from existing agent for Word, because that list is only for connections that use a key rather than Microsoft sign-in. Sign in again on the copy, or add the accounts under Settings.

Disconnecting. Disconnect on the step removes the primary Microsoft account from this agent. The confirmation reads Microsoft Word disconnected from this agent. If that was the only account, every Word step stops until someone signs in again. If other accounts remain, the oldest of them becomes primary, and the steps keep working against that account, even though the confirmation reads as if Word had been removed entirely. Other agents keep their own accounts, and the Microsoft Word card in chat is left as it is. To drop one named account and keep another, disconnect that row under Settings, then Integrations, rather than using Disconnect on the step.

Select the step and open Actions in the Details panel. The line under the title reads What this step does with the connected Microsoft Word account. On a step in the agent's main flow the list is a set of radio buttons, one action only, in this order: Find or create document, List documents, Get document, Insert blocks, Format runs, Replace text, Save document, Download document. There is no search box. The canvas summary shows the action's name, and the document title when you have typed one. It does not show a count such as 1 action enabled. A new step starts on Insert blocks.

Insert blocks then shows Word details. Document title is the file name without .docx, for example Job letter, Riverside House. Leave Document ID blank and the step finds that name, or creates it at the top of the OneDrive if it is not there. If you already have the file's ID from an earlier step, paste it into Document ID and the title is not used for the lookup. The help under the title says to leave the ID blank to find or create by name.

The body of the document is Blocks. Tick Bind blocks from incoming item when an Intelligence step has just written the letter or the report. The box fills with {{ item.json.blocks }}, and you leave the block list empty. The Intelligence step has to return that list. If it does not, Centrus warns you on the canvas. The warning names internal fields. You can ignore that wording and tick the bind box, then make sure the Intelligence step's output includes a blocks list. Untick the bind box only for a short fixed layout you type yourself, then click Add block.

Each block has a type: Heading 1, Heading 2, Heading 3, Paragraph, Bullet, Numbered, Image, Table, Page break or Page number. Prose blocks take the text, and can be Bold, Italic or Underline, with Colour, Size, Font, Alignment (left, centre, right or justify), Placement (body, header or footer) and spacing before and after (None, Tight, Line or Loose). Headings start bold. Consecutive numbered blocks are one list, and a heading or paragraph between them starts the next list at 1. The same is true of bullets. A page break starts the next block on a new page.

An Image block does not take text. Its bytes come from a file an earlier step downloaded, with Binary key left as attachment unless that step used another name. Placement can be Inline, Header, Footer or Float, with alignment, and for a float a wrap of None, Square, Tight or Top and bottom. Width is in pixels. On a float, Scale multiplies the picture's own width, and Inset X cm and Inset Y cm sit the picture in from the aligned edges. A Table can tick First row is a header. The rows are one line each, with cells separated by a vertical bar. The step appends these blocks to whatever is already in the file, then saves. It does not clear the file first, so a second run of the same agent adds the letter again.

Find or create document uses the same Document title. It looks at the top of the OneDrive for that name, then searches the drive for a file whose name matches exactly, ignoring letter case. If it finds one, it passes on the ID and the link and does not change the file. If it does not, it creates an empty .docx at the top of the drive. A name that already exists is tried again as the same name with (1), then (2). Characters that a file name cannot hold, such as a slash or a colon, are turned into spaces, and a trailing .docx is removed. An empty title becomes the name Document.

List documents returns one item, holding up to 50 .docx files from a search of the connected drive. The panel has no box for that cap, so a step on the main path always asks for 50. Names that do not end in .docx are dropped, so the list can be shorter than 50. Each row has the file's ID, title, created time, modified time and link. It does not pass on one item per file, so a Loop after it does not walk the files one by one. Get document needs Document ID. It returns the name, the link, the created and modified times, and the size. It does not return the words in the file.

Replace text shows Find and Replace with. Every match is replaced. The panel has no box to change only the first match. Format runs shows Match text. Paragraphs that contain that text are the ones that change. The panel does not offer colour, bold, italic or a font for this action, even though a call from an Intelligence step can pass those. On the main path, set the look on the blocks themselves when you insert them. If nothing matches, the step still succeeds and reports that it did not save. Save document writes the current file again. Insert blocks and Format runs already save, so you only need Save document when you want a save and nothing else. It needs Document ID.

Download document shows Download as, either Word document (.docx) or PDF. PDF is converted when the file is downloaded. OneDrive still stores the .docx. The file is passed on for the next step to attach or read, under the name Word already uses, unless a later step renames it. There is no box on the panel for a different file name. If Document ID is blank and Document title is filled in, the download looks the file up and can create it, the same way Find or create document does. To read the words, put a File Parser step after the download. Get document will not do that, because it only returns the name and the link. File Parser is covered under Steps an agent can use.

What the step passes on. Insert blocks passes on one item: the document ID, a second copy of that ID, the OneDrive link, and how many blocks were written. Download document passes on one item plus the file. List documents passes on one item whose list holds the files. Find or create document and Get document pass on one item with the ID and the link. Later steps reach those fields through Step data references. One visit writes one document, from the first item it receives, not one block for each row of a list. To write one document per job, put the Word step inside a Loop with batch size 1, described in Conditions, loops and approvals.

As a tool for an Intelligence step. Connect a Word step to the Tools side of an Intelligence step and Actions becomes a searchable list where you can tick several. The AI decides when to call each one and fills in the fields itself. The canvas summary is the first action's name plus a count when there are more, such as Find or create document +2, not the full list of names.

Job finished

Job status changed

Draft the letter

GPT-5.6 Terra

Document tools

Find or create document +2

1

1. 1The Word step attached to the Intelligence step as a tool.
2. 2Actions: the Word actions the AI may call. Here, find or create, insert and download.
3. 3Pause for approval: each call the AI makes waits for someone to approve it in the Runs panel.

Pause for approval appears on every Word step but only applies to calls an AI makes, so it has no effect on a step in the main flow. To ask someone before a main-flow step writes a document, put an Approval step in front of it.

Microsoft Word has no trigger of its own. Nothing in OneDrive starts a run when a document changes. An agent that should write a letter after a job is finished starts from a BigChange webhook, then a BigChange REST step if it needs the job, then the Word step. An agent that should write on a timetable starts from a Schedule. An agent that should answer a question about a contract starts from Email received, then downloads the document. The general picture for every system is in Start an agent from a system alert. Schedules are in Run an agent on a schedule. Mail is in Start an agent when an email arrives.

Job finished

Job status changed

Write the document

Insert blocks · Job letter, Riverside House

1. 1Connection on the BigChange webhook. This is the BigChange REST connection. Word has no trigger of its own, and this webhook does not use the Word account.
2. 2Event types: the events that start a run. Only Job status changed is ticked.
3. 3Set this up in BigChange: the steps to follow in BigChange and the address to paste there.
4. 4Simulate webhook: runs the agent once with a sample alert. A Word step after it still writes the document.

What the Word step should read from the alert. A BigChange Job status changed alert hands on the ID of the job, which is a number. Document title is text, so you can build a name from a later Get job, for example a title that includes the job reference J-10482. The usual pattern is Get job in between, then an Intelligence step that turns the job into blocks, then Insert blocks with Bind blocks from incoming item ticked. Setting up the webhook, the full list of events, and the status filter are covered in BigChange REST in Agent Builder.

A schedule has no record attached. The first step after it has to go and fetch the jobs or the sites, usually with a list action, and a Loop if each one needs its own document. Email received hands the new message to the next step. The Word step does not read that message by itself. Download the contract, let File Parser read the file, and let an Intelligence step draft the reply. A simulated BigChange alert is a real run: Insert blocks, Replace text and Find or create document do change OneDrive, and the run uses credits. Alerts and schedules only start runs once the agent is published. Simulate webhook and Run now work on drafts.

Job finished

Job status changed

Fetch the job

Get job

Write the letter

GPT-5.6 Terra

Write the document

Insert blocks · Job letter, Riverside House

Job letter after a visit files a customer letter when a job is completed. Job finished is a BigChange webhook with Job status changed ticked, and the status filter in BigChange set to the completed statuses. Fetch the job uses Get job, so the agent has the contact, the site and the engineer: job J-10482, a boiler service at Riverside House for Northgate Housing, with Dylan Hughes on the job. Write the letter turns that into blocks: a heading, a short paragraph, and a table of what was done. Write the document is Insert blocks, with Document title set to Job letter, Riverside House and Bind blocks from incoming item ticked. The file is created in the office OneDrive the first time, and later runs append to the same file, so give each visit its own title if you do not want them stacked. Each finished job costs five credits or a little more. To email the file as well, add Download document and an Outlook Send email after it. The BigChange side of the alert is in BigChange REST in Agent Builder.

Monday at 08:00

Weekly · Mon at 08:00

This week's jobs

List jobs

Each job

Batch size 1

Write the summary

GPT-5.6 Terra

Site summary

Insert blocks · Site summary

Weekly site summaries writes one document per job completed in the past week, at 08:00 every Monday. This week's jobs uses BigChange REST List jobs for that date window, and passes on one item per job: Riverside House on Monday, Harbour View Apartments on Wednesday, 12 High Street on Friday. Each job is a Loop with batch size 1, because a Word step writes from the first item it receives and would otherwise ignore the rest. Write the summary drafts the blocks for that one job. Site summary is Insert blocks, with Document title set from the site name on the item, and the blocks bound from Write the summary. Twelve jobs mean twelve documents, and twelve passes of the Word step. The list costs 1 credit however many rows it returns. The schedule is free. The Loop itself is free. Each document costs another credit, and the writing step is charged on every pass.

Contract question

Outlook · Inbox

Download the contract

Download document · Northgate Housing contract

Read the clause

Contract clause

Draft the reply

GPT-5.6 Terra

Reply

1 action enabled

Answer a contract question replies when a message about the Northgate Housing contract lands in the inbox. Contract question is Email received on the agent's Outlook connection, watching Inbox, with Subject contains set to contract. Word does not watch the mailbox. Download the contract is Download document, with Document title set to Northgate Housing contract and Download as left as Word document (.docx). Read the clause is a File Parser step, which reads the file and pulls out the sentence the message asked about, such as the response time at Riverside House. Draft the reply writes a short answer from that sentence and does not invent a term that was not in the file. Reply is Outlook Reply to email, so the answer stays in the same conversation. Get document is the wrong action here: it returns the link, not the wording. Each matching message costs six credits or a little more. Outlook's side of the reply is in Microsoft Outlook in Agent Builder.

A dry run is the safe way to try a Word step that writes. Open Runs in the toolbar, click Run now and choose Dry run (no actions performed). Read actions such as List documents and Get document call Microsoft for real, so you see real file names. Download document also calls Microsoft for real, because it is treated as a read, and you receive the file. If that step has a title and no document ID, it can create the file while it looks it up, including on a dry run. Write actions, Find or create document, Insert blocks, Format runs, Replace text and Save document, are skipped when they are the step's own action. The step's summary starts with DRY RUN and says the change was not performed, and OneDrive is left as it is. Run for real performs every action, including the writes.

{
  "handles": {
    "main": 1
  },
  "items": {
    "main": [
      {
        "dryRun": true,
        "documentTitle": "Job letter, Riverside House",
        "blocks": 6
      }
    ]
  }
}

Open a step in the run to see its output. The panel shows the first 50 items of each output, and later steps still receive all of them. A skipped insert does not add text to the file. A dry run costs 1 credit for the whole run. A simulated BigChange alert is not a dry run, so test Insert blocks with Run now first. For Run now, dry runs and the Runs panel in full, see Test an agent before it goes live.

A Microsoft Word step costs 1 automation credit each time it runs successfully, whatever the action and however long the document. A step that fails costs nothing. When the step is a tool, each call the AI makes costs 1 credit. Word has no trigger. A run started by a schedule, by Email received, or by a BigChange webhook still costs 1 credit for the run, like any other run, and those triggers themselves are free. Find or create document inside an insert or a download is part of that same step. It is not a second credit.

Inside a Loop, the Word step is charged on every pass, so a Loop over 40 jobs that writes a document for each one costs 40 credits for that step. One List documents is not a way to walk every file, because it returns a single list capped at 50. For allowances, limits and how to see what each run cost, see Automation credits and usage limits.

• Two connections. The agent's Microsoft account and each person's Microsoft Word card in chat are separate. Connecting one does not connect the other. Chat works in the signed-in person's own files. An agent writes to the OneDrive connected on the agent.
• The signed-in account only. The step uses the account chosen at Microsoft's account page. It does not offer a shared library you can open but are not signed in as. SharePoint is a different step.
• Files land at the top of the drive. Find or create document, and an insert or download that looks up by title, creates a missing file at the top of that OneDrive. There is no folder box. A file that already lives in a folder is still found when the name matches exactly.
• Only .docx. The list and the create actions use Word's .docx files. An older .doc file is not listed and is not opened.
• Append, not replace. Insert blocks adds to the file that is already there. Run the same title twice and the letter appears twice. Use a title that changes with the job, or Replace text when you are filling a phrase you put in the file on purpose.
• One document per visit. A Word step writes from the first item it receives. Per-job documents need a Loop with batch size 1. List documents returns one item with at most 50 files, not one item per file.
• Reading the words. Get document returns the name, the link, the times and the size. To use the wording in a reply, Download document and then File Parser. PDF is converted at download. OneDrive still stores the .docx.
• The look of the text. On Insert blocks you set bold, italic, underline, colour, size, font, alignment and spacing on each block. Format runs on the main path only asks for Match text. It does not show those look controls.
• Images. An image block needs a file already downloaded by an earlier step. A picture address on the web is not fetched. There is no chart inside the document. A picture of a chart would have to arrive as a downloaded image.
• Per-user integration mode. Word only works with the agent's own connection. The Account picker still applies. The note under Integration mode in Settings names Outlook and Gmail, not Word.
• Sign-in lasts 10 minutes. If you leave Microsoft's page open longer than that, the sign-in expires and Connect has to be started again. The permission you accept covers every file the account can open, not only Word documents.
• Published agents only. A schedule, a BigChange webhook and Email received only start runs once the agent is published. Run now works on drafts.

• Microsoft Word not connected for this agent. Open the step's Connection section and click Connect. If you have duplicated the agent, the copy needs its own sign-in. A chat connection on the Integrations page does not count.
• Microsoft Word account "primary" is no longer connected to this agent. The word in quotes is the account reference stored on the step, and it may be a longer id for an account you added later. The Account list also warns This node's account is no longer connected to this agent. Choose Primary account (default) or another account, or sign that one in again.
• Save this workflow as a draft first, then connect the account. Click Save draft, then Connect.
• Failed to start Microsoft Word connection. Centrus could not open Microsoft. Try Connect again.
• You return to the agents list and nothing explains the failure. The sign-in was refused, it expired after 10 minutes, or it was closed early. Nothing was saved. Open the agent and click Connect again.
• Set a document title (find or create) or a document ID before inserting blocks. Insert blocks had neither. Type a Document title, or paste a Document ID from an earlier step.
• No blocks to insert. The block list was empty, or every prose block had no text. Tick Bind blocks from incoming item when the previous step wrote the blocks, or add a block with text. Image, table, page break and page number blocks do not use text.
• No image bytes on the item. An image block ran before any step had downloaded the picture. Download the file first, then insert. The message names an internal download action. You can ignore that name.
• A document title is required. Find or create document had a blank title.
• find is required. Replace text had an empty Find box. The message uses the internal field name. Type the phrase in Find.
• documentId is required. Get document, Format runs, Replace text or Save document had no Document ID, and no earlier step had passed one on.
• Failed to get document, Failed to list documents, Failed to save Word document, Failed to download Word document or Failed to create document. Microsoft refused the call. The message after the colon is Microsoft's. A create that fails after trying the name, the name (1) and the name (2) ends on Failed to create document. Check the account still has room, and that the name is one Word will accept.
• Word download did not return document bytes. The download ran but the file was empty. Try Get document with the same ID to see whether the file is still there.
• No document to download. Download document had no title, no ID, and nothing earlier in the run carried an ID. The step succeeds and passes on an empty result, so a later File Parser has nothing to read.
• The letter appears twice. Insert blocks appends. The same title on a second run adds the blocks again. Change the title per job, or replace a known phrase instead.
• A list stops at 50. List documents never returns more than 50 .docx files, and the panel has no box to raise that. A Loop does not split that list into one item per file.
• An alert never starts the agent. Word does not listen for alerts. Check the trigger on the same agent: the agent must be published, and a BigChange webhook must be ticked and added in BigChange. See BigChange REST in Agent Builder.
• The step still uses the office account after you switch to Per-user. That is expected. Word has no per-user credentials. Sign the account in on the agent, and leave Integration mode on Agent-level.

The Microsoft Word step has 8 actions. Three read the account and five change it. They call Microsoft Graph at https://graph.microsoft.com/v1.0, as the account you connected on the agent. Insert blocks, Format runs, Replace text and Save document all save with the same upload. Download document uses the PDF address when Download as is PDF.