Explainer

Cowork plugins explained for SharePoint AI Skills practitioners

Cowork plugins are M365 App Packages that wrap SKILL.md files plus optional connectors. Your existing SharePoint AI Skill is most of a Cowork plugin already. Here is how the pieces fit.

Daniel Anderson11 min read

Microsoft announced Cowork plugins on 5 May 2026. The headline detail most coverage missed: the plugin format is built on the same Agent Skills open standard that SharePoint AI Skills already use. If you have written a SharePoint AI Skill, you have most of a Cowork plugin already.

This article is the practitioner explainer. What Cowork plugins are, how they relate to your existing SharePoint AI Skills, the three plugin patterns to know, the four Microsoft plugins shipping now, and the path from your SKILL.md to a tenant-deployable plugin package.

The companion how-to is in how to ship your SharePoint AI Skill as a Cowork plugin. The broader cross-platform context lives in the Agent Skills standard. This article is the orientation piece for both.

What is a Cowork plugin, really?

A Cowork plugin is a Microsoft 365 App Package. That is the same .zip format Microsoft uses for Teams apps, Copilot agents, and Office add-ins. The plugin extends Cowork by packaging up new capabilities and shipping them through the standard Microsoft 365 distribution and governance pipeline.

A plugin .zip contains:

Once installed, the plugin's skills become available to Cowork users in the tenant. Cowork loads them at the start of each conversation alongside its 13 built-in skills and any custom skills the user has in their OneDrive.

The crucial point: the SKILL.md files inside a plugin are the same format you already use for SharePoint AI Skills. Same YAML frontmatter, same Markdown body, same instructions, same examples. The plugin layer is a wrapper for distribution and governance. The skills inside are unchanged.

Your SharePoint AI Skill is 80% of a Cowork plugin

This is the part that matters most for sharepointaiskills.com readers. If you have a working SharePoint AI Skill, the Markdown file is portable. The work to turn it into a plugin is the wrapper, not the content.

What you already have:

What you need to add to ship it as a Cowork plugin:

That is it. The SKILL.md goes in untouched. The complete how-to is in how to ship your SharePoint AI Skill as a Cowork plugin, which walks through each step with the actual file structure.

The runtime context does change between surfaces. A SharePoint AI Skill runs against a single site's content. A Cowork plugin runs against the user's full M365 environment (Outlook, Teams, OneDrive, calendar, plus any connectors the plugin declares). Steps in your skill that assume site-level context may need light editing when you target Cowork. The format is the same; the runtime is different. We covered that distinction in detail in Cowork Skills and SharePoint AI Skills.

The three plugin patterns

Microsoft's Cowork plugin docs describe three packaging patterns. Pick the one that fits the work.

Pattern 1: Skills only (no connector)

Best for prompt-based workflows that work entirely with content already accessible to Cowork: documents, files, email, calendar, Teams.

Example structure:

my-skills-pack.zip
├── manifest.json          # agentSkills only, no agentConnectors
├── color.png
├── outline.png
└── skills/
    ├── meeting-prep/SKILL.md
    └── briefing-doc/SKILL.md

This is the pattern that maps most directly to existing SharePoint AI Skills. A SharePoint AI Skill that uses content from a site can become a Cowork plugin that uses content from the user's M365 environment with relatively little adaptation. No external systems, no auth, just the SKILL.md plus the wrapper.

Pattern 2: Skills plus remote connector

Best for skills that need to reach external data sources or APIs. The plugin includes both SKILL.md files and a connector definition pointing at a remote MCP server (Model Context Protocol).

Example structure:

my-data-skills.zip
├── manifest.json          # agentSkills + agentConnectors
├── color.png
├── outline.png
└── skills/
    ├── analysis-workflow/SKILL.md
    └── reporting-workflow/SKILL.md

The connector handles authentication (typically OAuth or API key) and exposes the external data to the skills inside the plugin. This is the pattern Microsoft uses for Fabric IQ and the Dynamics 365 plugins, and the pattern third-party launch partners (LSEG, Miro, monday.com, S&P Global Energy) will use.

Pattern 3: Connector only

Best when the data source is the value and Cowork's built-in skills are sufficient. The plugin only declares a connector. Cowork's existing skills (Word, Excel, Email, Deep Research, etc.) consume the connector's data without needing custom skill files.

Example structure:

my-connector.zip
├── manifest.json          # agentConnectors only, no agentSkills
├── color.png
└── outline.png

This is the lightest plugin to ship. Useful when you have an internal API that Cowork users would benefit from, but the workflows around it are generic enough that the built-in skills handle them.

From the tenant

Most teams' first plugin should be Pattern 1 (Skills only). Pick a SharePoint AI Skill you have already shipped, package it for Cowork, and learn the deployment loop on something that already works. Connectors add complexity (auth, network, error handling) that you do not want to debug at the same time as learning the manifest format.

The four Microsoft plugins shipping now

Microsoft has built four native plugins for Cowork that ship as part of the May 2026 update.

PluginWhat it connects toWhat it enables
Fabric IQMicrosoft Fabric and Power BIQuery datasets, generate reports, access business intelligence across your Fabric workspace
Dynamics 365 SalesDynamics 365 SalesQuery leads, opportunities, accounts, pipeline data
Dynamics 365 Customer ServiceDynamics 365 Customer ServiceManage cases, knowledge articles, support workflows
Dynamics 365 Finance & OperationsDynamics 365 ERPFinancial data, supply chain, operations workflows

These plugins use Microsoft Entra ID authentication. After the plugin is added to a tenant, users select a target environment (Sales database, Fabric workspace, etc.) during the initial sign-in flow.

The third-party launch partners (LSEG, Miro, monday.com, and S&P Global Energy) are rolling out in the weeks following the May 5 announcement. They use the same M365 App Package format as the Microsoft plugins.

How distribution and governance work

Cowork plugins distribute through two channels.

Microsoft 365 App Store, for public availability. Plugins published here are visible to all M365 customers (subject to admin approval at the tenant level). Microsoft and partner plugins live here. Custom plugins built by your organisation can also be published here via Partner Center if you want to make them broadly available.

Sideload via Admin Centre, for internal use only. Upload the .zip package directly through Microsoft 365 Admin Centre → Manage Apps → Upload custom app. The plugin becomes available to users in the tenant without going through the App Store. This is the path most organisations will use for plugins built around their own internal systems.

Sideloaded plugins can also be deployed via API:

POST /users/titles
Content-Type: application/zip
Body: <your-package.zip>

The governance layer is the standard Microsoft 365 admin model. Admins control which plugins are available, which users have access, and which tenants the plugin operates in. Plugins inherit the user's permissions and Entra ID identity. None of this differs from how Teams apps or Copilot agents are governed today.

What this means for your SharePoint AI Skills work

Three implications worth naming.

One: your existing investment ports forward. Every SharePoint AI Skill you have written can become a Cowork plugin with light packaging work. The SKILL.md files do not need to be rewritten. They get wrapped.

Two: the distribution model expands. SharePoint AI Skills are site-scoped. A Cowork plugin is tenant-scoped. If your team has built a Skill that would be useful across multiple sites or for users working outside SharePoint, packaging it as a Cowork plugin is the way to widen the audience.

Three: the same SKILL.md is now an industry-portable artefact. The Agent Skills open standard runs in nine AI tools today (Claude Code, Claude.ai Projects, VS Code Copilot, Gemini CLI, JetBrains Junie, OpenAI Codex, Cursor, Cowork, AI in SharePoint). One file, multiple destinations. We cover that bigger picture in the Agent Skills standard.

The practical question is: which of your SharePoint AI Skills should be your first Cowork plugin? Pick the one that is most useful to a single user across multiple M365 apps (calendar plus email plus documents, for example). That is where Cowork plugins shine. Site-scoped work stays a SharePoint AI Skill. Personal, cross-app work becomes a Cowork plugin.

The how-to walkthrough is the next read: how to ship your SharePoint AI Skill as a Cowork plugin in 30 minutes.

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Frequently asked questions

Answers to the questions we hear most

What is a Copilot Cowork plugin?

A Cowork plugin is a Microsoft 365 App Package: the same .zip format used by Teams apps, Copilot agents, and Office add-ins. The package contains a manifest, optional skill files (SKILL.md), and optional connector definitions. When installed in a tenant, the plugin makes its skills and connectors available to Cowork users.

How are Cowork plugins different from SharePoint AI Skills?

A SharePoint AI Skill is a single SKILL.md file living at /Agent Assets/Skills/<name>/SKILL.md in a SharePoint site, scoped to that site. A Cowork plugin is a packaged distribution that can contain one or more SKILL.md files plus optional connectors, deployed at the tenant level for use across the user's full M365 environment. The plugin is the wrapper; the SKILL.md inside it is the same format you already write.

Do Cowork plugins use the same SKILL.md format as SharePoint AI Skills?

Yes. Both use the Agent Skills open standard: a Markdown file with YAML frontmatter (name, description) plus instructions in the body. The same file can run as a SharePoint AI Skill or as part of a Cowork plugin with light editing for runtime differences.

What can a Cowork plugin contain?

Three patterns. Skills only: a manifest plus one or more SKILL.md files for prompt-based workflows. Skills plus connector: skills paired with a remote MCP server for accessing external data or APIs. Connector only: just the connector definition, useful when Cowork's built-in skills can already work with the data source.

Where do Cowork plugins live once installed?

Microsoft and partner plugins install from the Microsoft 365 App Store and become available across the tenant. Custom plugins can be sideloaded through the Microsoft 365 Admin Centre under Manage Apps. Custom Cowork skills (without the plugin wrapper) live in the user's OneDrive at /Documents/Cowork/Skills/<name>/SKILL.md, but those are individual user skills, not packaged plugins.

Which Microsoft plugins ship natively with Cowork?

Four Microsoft plugins are available now or shipping shortly: Fabric IQ (connects Cowork to Microsoft Fabric and Power BI for querying datasets and generating reports), Dynamics 365 Sales (leads, opportunities, accounts, pipeline), Dynamics 365 Customer Service (cases, knowledge articles, support workflows), and Dynamics 365 Finance & Operations (financial data, supply chain, ERP workflows).

Which third-party plugins are coming?

Microsoft announced LSEG (London Stock Exchange Group), Miro, monday.com, and S&P Global Energy as launch partners on 5 May 2026, with more to come. Third-party plugins distribute through the Microsoft 365 App Store like the Microsoft ones, with the same install and governance model.

Can our organisation build a custom plugin?

Yes. Custom plugins use the same M365 App Package format as Microsoft and partner plugins. Build the SKILL.md files, write a manifest, package as a .zip, then either sideload through the Admin Centre for internal use or publish to the Microsoft 365 App Store via Partner Center. The how-to lives in how to ship a Cowork plugin from a SharePoint AI Skill.

Do Cowork plugins respect SharePoint and tenant permissions?

Yes. Plugins inherit the user's existing Microsoft 365 permissions and use Microsoft Entra ID for authentication. They can only access data the asking user is permitted to see. The plugin layer adds distribution and governance; it does not bypass identity or compliance controls.

What licence do Cowork plugins require?

Microsoft 365 Copilot. Plugins are part of Cowork, which is itself part of the Microsoft 365 Copilot offering. There is no separate plugin SKU. To use Cowork during preview, the tenant administrator must also opt into the Microsoft 365 Frontier program.

Daniel Anderson

Founder, ShiftF5.ai · Microsoft Partner

Microsoft 365 consultant with twenty years in SharePoint, Copilot, and M365 AI enablement. Publisher of sharepointaiskills.com. I write about what actually ships in client tenants.

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