Brief
Canonical issue: microsoft/vscode-copilot-chat#5101
Cross-filed at the GitHub Copilot CLI repo because SKILL.md is a cross-tool format consumed by both VS Code Copilot Chat and Copilot CLI plugin install. The gap and the proposal apply identically here.
Summary (1 paragraph)
Custom agents (.agent.md) declare their capabilities in frontmatter — tools, mcp-servers, hooks, model. Skills (SKILL.md) cannot — they currently support only name, description, argument-hint, user-invocable, disable-model-invocation. The asymmetry forces every consuming agent to know and re-declare a skill's capability requirements, leading to silent under-capability and ecosystem-specific workarounds. Proposed: extend SKILL.md frontmatter with the same optional fields, with skill-declared tools/mcp-servers unioning with consuming agents, skill-declared hooks activating with the skill, and model as advisory.
Why filed here
copilot plugin install loads SKILL.md files; the same capability-declaration gap applies to the CLI surface. Closing it natively at the SKILL.md level reduces the need for plugin-level bundling workarounds (whole plugin enables together, coarser than per-skill) and aligns skill composability across both surfaces.
See the canonical issue for full proposal, use cases, inheritance semantics, and references.
Brief
Canonical issue: microsoft/vscode-copilot-chat#5101
Cross-filed at the GitHub Copilot CLI repo because SKILL.md is a cross-tool format consumed by both VS Code Copilot Chat and Copilot CLI plugin install. The gap and the proposal apply identically here.
Summary (1 paragraph)
Custom agents (
.agent.md) declare their capabilities in frontmatter —tools,mcp-servers,hooks,model. Skills (SKILL.md) cannot — they currently support onlyname,description,argument-hint,user-invocable,disable-model-invocation. The asymmetry forces every consuming agent to know and re-declare a skill's capability requirements, leading to silent under-capability and ecosystem-specific workarounds. Proposed: extend SKILL.md frontmatter with the same optional fields, with skill-declaredtools/mcp-serversunioning with consuming agents, skill-declaredhooksactivating with the skill, andmodelas advisory.Why filed here
copilot plugin installloads SKILL.md files; the same capability-declaration gap applies to the CLI surface. Closing it natively at the SKILL.md level reduces the need for plugin-level bundling workarounds (whole plugin enables together, coarser than per-skill) and aligns skill composability across both surfaces.See the canonical issue for full proposal, use cases, inheritance semantics, and references.