Microsoft Learn updated Skills overview for agents (GitHub Copilot) on 28 October 2026. Read with its companion pages on creating, uploading and managing skills, it describes something admins have not had to govern in Copilot Studio before: a reusable package of instructions, and optionally scripts, that one maker can share with named people and groups across the organization, and that other makers can drop into their own agents. The governance point is simple. Skills are becoming a supply chain inside your tenant, and the documentation describes how makers share them but not how admins control, review or audit that sharing.
Power Platform Engineer has already covered the harness these skills run on in The GitHub Copilot Harness Is Now the Microsoft Copilot Harness, and the built-in file skills in Copilot Studio Agents Now Create Files Users Can Download. This piece is about the skills makers write and share themselves.
What the documentation describes
Microsoft defines agent skills as “portable packages of instructions, scripts, and resources that give agents specialized capabilities and domain expertise.” The overview contrasts them with tools: “Unlike tools, which connect to external services, skills are self-contained sets of instructions and logic that you can create, share, and reuse across agents.”
| Aspect | What Learn says (read 10 November 2026) |
|---|---|
| Harness | Agents powered by the GitHub Copilot harness; the Customer Conversation harness has its own Generative and Topic skill types |
| Ways to add | “uploading an existing skill file or package, creating a skill from blank, or generating one with AI”, from the Build tab |
| Package contents | A ZIP that “must include a SKILL.md file” and “can optionally include supporting files, such as scripts, templates, and reference documents” |
| When it runs | The orchestration runtime “invokes a skill when a user’s request matches the skill’s purpose” |
| Built-in skills | Provided by the harness for CSV, Word, HTML, Markdown, PDF, PowerPoint and Excel files |
| Sharing | Marketplace sharing to “Only you” or “Specific users or groups in your organization”, labelled preview |
| Reuse model | The consuming agent “gets a snapshot of the skill while maintaining a reference to the original marketplace skill” |
| Billing | “Using, building, testing, and evaluating agents might consume Copilot Credits.” |
| Status | No preview label on the overview, create or upload pages; the marketplace sections are marked prerelease |
Sharing turns a maker artifact into a tenant asset
The Manage page states the purpose of marketplace sharing plainly: “You can share a skill you created so that you and other people in your organization can use it across Copilot Studio agents and other supported experiences.” The Share dialog offers two choices, Only you or specific users or groups, added by name or email address.
That is a maker decision. Nothing on the four skills pages describes a Power Platform admin center setting, an environment setting or a tenant switch that limits who can share a skill, or a step where an admin approves a skill before it appears for others. The only reference to admins in the consumption flow is the sentence “The skills available to you are the ones shared by admins or skill owners.” The phrase “and other supported experiences” also means a shared skill may travel beyond Copilot Studio agents, and the pages do not list those experiences.
For organizations that already run a review for connectors, custom connectors or solutions, this is the gap to close first. A skill shapes agent behaviour as directly as its instructions do, and a shared skill shapes the behaviour of every agent that adopts it.
Packages can carry scripts
The upload page accepts two formats: a Markdown file with the name and description in YAML front matter, or a ZIP package that can include “scripts, templates, and reference documents.” The overview adds that “Skills provide instructions; packages provide code libraries the agent can use for file and data operations.”
The pages do not say whether scripts inside an uploaded package are executed, where they would run, which identity they would run as, or what network or data access they would have. Until Microsoft documents that, treat any package that contains scripts as code, not as content, and route it through the same review your organization applies to code that touches business data.
Snapshots change how you think about versions
When a maker adds a marketplace skill, the agent receives a snapshot that keeps a reference to the original, and the maker receives “a skill update notification” when opening an agent that uses an older version. On the owner’s side, “When you edit and change a skill that you already shared, share the skill again to make the latest version available to those you previously shared it with.”
Two consequences follow. First, a fix to a shared skill does not reach consuming agents until the owner shares again and each consuming maker accepts the update, so several versions of the same skill can be live at once. Second, a change that is shared again can reach every consumer who accepts it. Neither is a reason to avoid skills, but both are reasons to know which agents use which skill version. The ALM questions raised in Copilot Chat Agents Just Got Topics, Evaluations, and ALM apply here too.
Download is not a backup of the package
The upload page says a downloaded skill comes back as “a Markdown file containing the skill name and description in YAML front matter, plus instructions.” It does not say that the scripts, templates or reference documents from a ZIP package are included. Deletion is permanent for that agent, and the Manage page advises downloading a skill first if it might be needed later. If a skill matters, keep the full package in a source repository your team controls rather than relying on the download.
Cost and invocation
Every skills page carries the same note: “The harness used to build this agent uses usage-based billing. Using, building, testing, and evaluating agents might consume Copilot Credits.” Skills are invoked by the orchestrator “based on the user’s message and the skill’s description,” so a vague description in a widely shared skill can change how often, and in how many agents, it is pulled into a conversation. The documentation does not break out skill invocation as its own billing line.
What the documentation does not cover yet (as of 10 November 2026)
- Any admin control over who can share skills, or over the skills marketplace as a whole.
- Whether scripts in an uploaded package run, where they run, under which identity, and with what data or network access.
- Where skills and packages are stored, and whether that storage follows the environment’s region and data policies.
- Whether skills move with solutions between environments, and how they appear in pipelines.
- Audit or inventory: which agents use a shared skill, and which version each one holds.
- File size limits for skill files and packages.
- Which “other supported experiences” can consume a shared skill.
- Whether a downloaded skill includes the supporting files of a ZIP package.
Admin checklist
- Decide whether marketplace sharing (preview) is acceptable in production environments while it carries the prerelease label.
- Publish a short skills standard for makers: naming, description quality, what a skill may and may not instruct an agent to do.
- Require review for any package that contains scripts, treated as code until Microsoft documents how scripts execute.
- Ask makers to share skills with security groups rather than individuals, so access can be removed in Entra ID.
- Keep the authoritative copy of every shared skill in a repository with change history, not in the download from Copilot Studio.
- Track which agents consume each shared skill and which snapshot they hold, and set an expectation for accepting update notifications.
- Watch Copilot Credit consumption for agents that adopt widely shared skills, using the approach in The Harness Is the Price Tag.
- Recheck the four skills pages before rollout; the marketplace sections are prerelease and may change.
Sources
- Skills overview for agents (GitHub Copilot), Microsoft Learn, updated 28 October 2026
- Create a skill for an agent (GitHub Copilot), Microsoft Learn, updated 21 October 2026
- Add and manage an uploaded skill (GitHub Copilot), Microsoft Learn, updated 21 October 2026
- Manage and delete skills in an agent (GitHub Copilot), Microsoft Learn, updated 21 October 2026
- What’s new in Copilot Studio, Microsoft Learn, updated 4 November 2026