feat(skill): render skills as slash commands in available items list

Skills now appear as <command> items with / prefix (e.g., /review-work)
instead of <skill> items, making them discoverable alongside regular
slash commands in the skill tool description.

src/tools/skill/tools.test.ts

@@ -384,7 +384,7 @@ describe("skill tool - ordering and priority", () => {
     }
   }
 
-  it("lists skills before commands in available_items", () => {
+  it("shows skills as command items with slash prefix in available_items", () => {
     //#given: mix of skills and commands
     const skills = [
       createMockSkillWithScope("builtin-skill", "builtin"),
@@ -398,16 +398,17 @@ describe("skill tool - ordering and priority", () => {
     //#when: creating tool with both
     const tool = createSkillTool({ skills, commands })
 
-    //#then: skills should appear before commands
+    //#then: skills should appear as <command> items with / prefix, listed before regular commands
     const desc = tool.description
-    const skillIndex = desc.indexOf("<skill>")
+    expect(desc).toContain("<name>/builtin-skill</name>")
-    const commandIndex = desc.indexOf("<command>")
+    expect(desc).toContain("<name>/project-skill</name>")
-    expect(skillIndex).toBeGreaterThan(0)
+    expect(desc).not.toContain("<skill>")
-    expect(commandIndex).toBeGreaterThan(0)
+    const skillCmdIndex = desc.indexOf("/project-skill")
-    expect(skillIndex).toBeLessThan(commandIndex)
+    const regularCmdIndex = desc.indexOf("/project-cmd")
+    expect(skillCmdIndex).toBeLessThan(regularCmdIndex)
   })
 
-  it("sorts skills by priority: project > user > opencode > builtin", () => {
+  it("sorts skill-commands by priority: project > user > opencode > builtin", () => {
     //#given: skills in random order
     const skills = [
       createMockSkillWithScope("builtin-skill", "builtin"),
@@ -421,10 +422,10 @@ describe("skill tool - ordering and priority", () => {
 
     //#then: should be sorted by priority
     const desc = tool.description
-    const projectIndex = desc.indexOf("project-skill")
+    const projectIndex = desc.indexOf("/project-skill")
-    const userIndex = desc.indexOf("user-skill")
+    const userIndex = desc.indexOf("/user-skill")
-    const opencodeIndex = desc.indexOf("opencode-skill")
+    const opencodeIndex = desc.indexOf("/opencode-skill")
-    const builtinIndex = desc.indexOf("builtin-skill")
+    const builtinIndex = desc.indexOf("/builtin-skill")
 
     expect(projectIndex).toBeLessThan(userIndex)
     expect(userIndex).toBeLessThan(opencodeIndex)
@@ -468,7 +469,7 @@ describe("skill tool - ordering and priority", () => {
     expect(tool.description).toContain("Skills listed before commands")
   })
 
-  it("uses <available_items> wrapper with unified format", () => {
+  it("uses <available_items> wrapper with unified command format", () => {
     //#given: mix of skills and commands
     const skills = [createMockSkillWithScope("test-skill", "project")]
     const commands = [createMockCommand("test-cmd", "project")]
@@ -476,10 +477,12 @@ describe("skill tool - ordering and priority", () => {
     //#when: creating tool
     const tool = createSkillTool({ skills, commands })
 
-    //#then: should use unified wrapper
+    //#then: should use unified wrapper with all items as commands
     expect(tool.description).toContain("<available_items>")
     expect(tool.description).toContain("</available_items>")
-    expect(tool.description).toContain("<skill>")
+    expect(tool.description).not.toContain("<skill>")
     expect(tool.description).toContain("<command>")
+    expect(tool.description).toContain("/test-skill")
+    expect(tool.description).toContain("/test-cmd")
   })
 })

src/tools/skill/tools.ts

@@ -45,23 +45,24 @@ function formatCombinedDescription(skills: SkillInfo[], commands: CommandInfo[])
 
   const allItems: string[] = []
 
-  // Sort and add skills first (skills before commands)
+  // Skills rendered as command items (skills are also slash-invocable)
   if (skills.length > 0) {
     const sortedSkills = [...skills].sort((a, b) => {
       const priorityA = scopePriority[a.scope] || 0
       const priorityB = scopePriority[b.scope] || 0
-      return priorityB - priorityA // Higher priority first
+      return priorityB - priorityA
     })
     sortedSkills.forEach(skill => {
       const parts = [
-        "  <skill>",
+        "  <command>",
-        `    <name>${skill.name}</name>`,
+        `    <name>/${skill.name}</name>`,
         `    <description>${skill.description}</description>`,
+        `    <scope>${skill.scope}</scope>`,
       ]
       if (skill.compatibility) {
         parts.push(`    <compatibility>${skill.compatibility}</compatibility>`)
       }
-      parts.push("  </skill>")
+      parts.push("  </command>")
       allItems.push(parts.join("\n"))
     })
   }