User-defined skill with same name as built-in skill causes invocation conflict

[sethseeman]

Description

When a user-defined skill shares the same name as a built-in skill (e.g. research), invoking the skill via the skill tool is unreliable. The built-in skill can take precedence over the user-defined skill, causing the user's custom skill to be ignored and an error to be thrown.

Steps to reproduce

1. Create a user-defined skill named research in ~/.claude/skills/research/SKILL.md
2. Start a Copilot CLI session — the skill appears in <available_skills> with <location>user</location>
3. Invoke the skill with the skill tool: skill: "research"
4. Observe that the invocation sometimes loads the built-in research behavior instead of the user-defined skill, or throws an error

Expected behavior

User-defined skills should take clear precedence over built-in skills of the same name, or there should be a namespacing mechanism to disambiguate (e.g. user:research vs builtin:research).

Actual behavior

The built-in skill intermittently overrides the user-defined skill, causing the custom skill content to be ignored. The user has no way to disable or override the built-in skill.

Environment

• Copilot CLI version: 1.0.8
• OS: Windows 11
• Built-in skills that conflict: analyze, design, document, fix, investigate, research, security, test, verify

Suggested fix

Either:

• Allow user-defined skills to override built-in skills of the same name
• Provide a configuration option to disable specific built-in skills
• Namespace built-in vs user skills to prevent collisions

[examon]

This should be resolved as of v1.0.17. Skill resolution was updated so user-defined skills take precedence over built-in skills with the same name, so this naming conflict should no longer occur. If you're still seeing this on v1.0.17 or later, please reopen with repro steps.