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api-and-interface-design

Guides stable API and interface design. Use when designing APIs, module boundaries, or any public interface. Use when creating REST or GraphQL endpoints, defining type contracts between modules, or establishing boundaries between frontend and backend.

Agent Skill from addyosmani/agent-skills

Copilot Studio

Passes documented load rules

No documented load rule failed.

Microsoft 365 Copilot Preview, Frontier tenants only

Passes documented load rules

No documented load rule failed.

An agent can have at most 8 skills. Custom skills aren't available in tenants that use Microsoft Purview Information Barriers.

Compatible isn't the same as safe. These verdicts only say whether a skill's files follow Microsoft's documented load rules. The checker reads files and never runs them, and it doesn't review what a skill or its scripts actually do. Read a skill's instructions and scripts before you add it to an agent.

Standards signals

Meets the agentskills.io required fields.

FrontmatterPresent and parsed
Spec: frontmatter
nameMeets the spec (1-64 chars, a-z 0-9 hyphens)
Spec: name
descriptionPresent, 1-1,024 characters
Spec: description
compatibilityAbsent or under 500 characters
Spec: compatibility
Name matches folderYes (api-and-interface-design)
Spec: name

Observed from the public SKILL.md at the commit above on 2026-10-23. Not a certification: AAIF and the Agent Skills project don't certify skills. Validate your own skill with skills-ref validate.

Source repoaddyosmani/agent-skills
Pathskills/api-and-interface-design/SKILL.md
Commit checkedaeac41d4d005
Repo licenseMIT
Files1
ScriptsNone
Instructions14,504 characters
Deepest folder0 below the skill folder
Installs (skills.sh)59,950
Rules version2026-10-22

Re-check the latest version How skill checks work

Is this wrong or out of date? Email us. Skills data built 2026-10-23; rules as of 2026-10-22.

Rule-based checks of public files against Microsoft's documented load rules, not tested in Copilot Studio or Microsoft 365 Copilot. Independent project, not affiliated with Microsoft.