Every Monday, we pull back the curtain on what’s shipping in Workato Enterprise MCP.
This week: The Microsoft 365 stack gets its data layer.
Two new pre-built MCP servers — Microsoft Excel and Microsoft OneDrive — bring the full file intelligence loop into your enterprise agent workflows. The catalog now stands at 31 production-ready servers.
What’s New
Microsoft Excel MCP Server – 8 tools
Read, update, and structurally manage Microsoft Excel workbooks stored in Microsoft 365. The Excel MCP Server gives AI assistants direct, structured access to workbooks in OneDrive for Business and SharePoint Online. It covers the full data layer: retrieve workbook structure and tabular data, append rows to trackers and tables, update specific ranges, manage worksheet tabs, and apply multi-step workbook changes atomically — all while preserving formulas, table structures, and Excel’s native permission model.
View Microsoft Excel documentation→
Microsoft OneDrive MCP Server – 14 tools
Find, organize, share, and manage files and folders in OneDrive for Business. The OneDrive MCP Server handles the file system layer that sits above individual applications. It covers file and folder discovery, content retrieval, creating and organizing folders, managing sharing and access, uploading externally generated files, copying, moving, renaming, and deleting files — all scoped to the authenticated user’s personal OneDrive for Business drive.
View Microsoft One Drive Documentation →
Why This Matters
Enterprise data doesn’t live in SaaS databases. It lives in spreadsheets.
Finance teams run month-end close in Excel. Sales ops tracks pipeline coverage in Excel. FP&A models headcount, variance, and revenue scenarios in Excel. The spreadsheet isn’t a legacy artifact — it’s the working layer where decisions actually get made. Until now, agents could read data from CRM, surface records from Jira, pull call transcripts from Gong — but they couldn’t touch the workbook where the actual numbers live. The Excel MCP Server closes that gap.
But reading and writing cells is only half the problem. The other half is finding the right workbook in the first place.
This is where OneDrive comes in. Enterprise OneDrive environments are sprawling — files scattered across folders, named inconsistently, last touched six months ago by someone who left the team. An agent that can write Excel data but can’t find the workbook is only half useful. The OneDrive MCP Server handles the discovery and file system layer: find the file, retrieve its content, confirm who has access, organize the folder. Then hand off to Excel to do the data work.
Together, these two servers complete the Microsoft 365 file intelligence loop. An agent can now locate a workbook in OneDrive, navigate its structure, read the data it needs, update specific ranges, append new records, and organize the result — all in a single agent session.
This also meaningfully expands Workato’s Microsoft 365 coverage. Between Outlook Email, Outlook Calendar, and now Excel and OneDrive, agents operating in Microsoft-first enterprises have a full productivity stack to work with cross-ecosystems.
- Microsoft Excel & Microsoft OneDrive — the complete M365 file intelligence loop: find the workbook in OneDrive, retrieve its structure and data in Excel, update ranges or append rows, save the result back to the right folder.
- Microsoft Excel & Salesforce Sales Cloud Explorer — pull opportunity data from Salesforce, write it to a pipeline tracker or revenue model in Excel, no manual exports required.
- Microsoft Excel & Google Sheets — agents operating across mixed ecosystems can now pull data from Sheets and write to Excel (or vice versa), covering hybrid deployments that use both platforms.
- Microsoft Excel & Microsoft Outlook — retrieve actuals from a financial model in Excel and compose a budget update email in Outlook — end-to-end reporting in a single workflow.
- Microsoft OneDrive & Microsoft Outlook — find an attachment shared by a colleague, retrieve its content, and draft a reply — without leaving the agent session.
Real-World Use Cases
Finance Analysts: Microsoft Excel
- “Show me the structure of our Q2 financial model. What worksheets are there and what named ranges does it use?
- “Update the actuals tab — replace the March revenue row with these numbers. Preserve the formula in column G.”
- “Append this month’s headcount data to the HC tracker table. Here are the new rows.”
- “Create a new worksheet called ‘May 2026’ and initialize it with the same headers as April.”
- “Apply these three updates atomically — append the new rows, update the summary formula, and rename the draft tab to Final.”
Design notes: The Excel server uses an optimistic concurrency model — all write operations require a session_id obtained from the most recent read. If a session expires between a read and a write, the write fails cleanly with no partial changes applied. The server operates on .xlsx workbooks in Microsoft 365 only — on-premises SharePoint, desktop Excel files, and legacy formats (.xls, .xlsm) are not supported. File discovery is intentionally excluded; use the OneDrive MCP Server to locate workbooks before operating on them with Excel.
Knowledge Workers and Project Managers: Microsoft OneDrive
- “Find the proposal I was working on last week. Pull up the file and show me who has access.”
- “Create a folder called ‘Project Apollo — Q2 2026’ and copy the standard project template into it.”
- “Show me all files in the Sales Materials folder that were updated since Monday.”
- “Share this deck with the finance and legal teams — give them view access.”
- “Move the old draft versions into an Archive subfolder. I don’t need them at the top level anymore.”
Design notes: The OneDrive server is scoped to the authenticated user’s personal OneDrive for Business drive. Files in SharePoint document libraries, team sites, or Teams channel folders may not be discoverable here — if search returns empty results, the file is likely SharePoint-backed. Delete operations send items to the recycle bin, not permanent deletion. Restoring deleted files requires the OneDrive web UI — restoration is not supported via the Microsoft Graph API for OneDrive for Business.
What Makes These Enterprise-Ready
- Verified User Authentication: All tool calls execute under the authenticated user’s Microsoft 365 identity — no shared service accounts, no attribution gaps. Every read and write is tied to the person who initiated it.
- Permission inheritance: Agents can only access files and workbooks the authenticated user’s M365 role grants them. The servers don’t elevate privileges or surface content outside the user’s existing access.
- Optimistic concurrency control (Excel): All write operations require a session_id from the most recent read. If a session expires between read and write, the write fails cleanly with no partial changes applied — no corrupted workbooks, no half-written rows.
- Safe deletion (OneDrive): Delete operations send items to the recycle bin, not permanent deletion. AI cannot irreversibly remove files. Restoration is available through the OneDrive web UI.
- Managed infrastructure: Workato hosts, scales, and maintains both servers. No Microsoft Graph API versions to track, no rate limits to manage, no infrastructure to provision.
- Composable: Chains with Outlook Email, Outlook Calendar, Salesforce Sales Cloud Explorer, Google Sheets, and the rest of the Workato MCP catalog for end-to-end cross-system workflows.
Get Started
Microsoft Excel and Microsoft OneDrive are available now for Workato customers with Enterprise MCP.
Install time: Minutes
Custom development: None
Deployment complexity: One-click activation
View Microsoft Excel documentation →
View Microsoft OneDrive documentation →
The full catalog — now 31 pre-built servers — is live here.
Try it in our self-service trial.
The bottom line: Other vendors are still announcing MCP roadmaps. We’re shipping production-ready servers every Monday.
See you next Monday.