refactor: merge skill tool into slashcommand to reduce system prompt size

src/tools/slashcommand/skill-formatter.ts

@@ -0,0 +1,130 @@
+import { dirname } from "node:path"
+import type { LoadedSkill } from "../../features/opencode-skill-loader"
+import { extractSkillTemplate } from "../../features/opencode-skill-loader/skill-content"
+import { injectGitMasterConfig as injectGitMasterConfigOriginal } from "../../features/opencode-skill-loader/skill-content"
+import type { SkillMcpManager, SkillMcpClientInfo, SkillMcpServerContext } from "../../features/skill-mcp-manager"
+import type { Tool, Resource, Prompt } from "@modelcontextprotocol/sdk/types.js"
+
+export async function extractSkillBody(skill: LoadedSkill): Promise<string> {
+  if (skill.lazyContent) {
+    const fullTemplate = await skill.lazyContent.load()
+    const templateMatch = fullTemplate.match(/<skill-instruction>([\s\S]*?)<\/skill-instruction>/)
+    return templateMatch ? templateMatch[1].trim() : fullTemplate
+  }
+
+  if (skill.path) {
+    return extractSkillTemplate(skill)
+  }
+
+  const templateMatch = skill.definition.template?.match(/<skill-instruction>([\s\S]*?)<\/skill-instruction>/)
+  return templateMatch ? templateMatch[1].trim() : skill.definition.template || ""
+}
+
+export async function formatMcpCapabilities(
+  skill: LoadedSkill,
+  manager: SkillMcpManager,
+  sessionID: string
+): Promise<string | null> {
+  if (!skill.mcpConfig || Object.keys(skill.mcpConfig).length === 0) {
+    return null
+  }
+
+  const sections: string[] = ["", "## Available MCP Servers", ""]
+
+  for (const [serverName, config] of Object.entries(skill.mcpConfig)) {
+    const info: SkillMcpClientInfo = {
+      serverName,
+      skillName: skill.name,
+      sessionID,
+    }
+    const context: SkillMcpServerContext = {
+      config,
+      skillName: skill.name,
+    }
+
+    sections.push(`### ${serverName}`)
+    sections.push("")
+
+    try {
+      const [tools, resources, prompts] = await Promise.all([
+        manager.listTools(info, context).catch(() => []),
+        manager.listResources(info, context).catch(() => []),
+        manager.listPrompts(info, context).catch(() => []),
+      ])
+
+      if (tools.length > 0) {
+        sections.push("**Tools:**")
+        sections.push("")
+        for (const t of tools as Tool[]) {
+          sections.push(`#### \`${t.name}\``)
+          if (t.description) {
+            sections.push(t.description)
+          }
+          sections.push("")
+          sections.push("**inputSchema:**")
+          sections.push("```json")
+          sections.push(JSON.stringify(t.inputSchema, null, 2))
+          sections.push("```")
+          sections.push("")
+        }
+      }
+      if (resources.length > 0) {
+        sections.push(`**Resources**: ${resources.map((r: Resource) => r.uri).join(", ")}`)
+      }
+      if (prompts.length > 0) {
+        sections.push(`**Prompts**: ${prompts.map((p: Prompt) => p.name).join(", ")}`)
+      }
+
+      if (tools.length === 0 && resources.length === 0 && prompts.length === 0) {
+        sections.push("*No capabilities discovered*")
+      }
+    } catch (error) {
+      const errorMessage = error instanceof Error ? error.message : String(error)
+      sections.push(`*Failed to connect: ${errorMessage.split("\n")[0]}*`)
+    }
+
+    sections.push("")
+    sections.push(`Use \`skill_mcp\` tool with \`mcp_name="${serverName}"\` to invoke.`)
+    sections.push("")
+  }
+
+  return sections.join("\n")
+}
+
+export { injectGitMasterConfigOriginal as injectGitMasterConfig }
+
+export async function formatSkillOutput(
+  skill: LoadedSkill,
+  mcpManager?: SkillMcpManager,
+  getSessionID?: () => string,
+  gitMasterConfig?: any
+): Promise<string> {
+  let body = await extractSkillBody(skill)
+
+  if (skill.name === "git-master" && gitMasterConfig) {
+    body = injectGitMasterConfigOriginal(body, gitMasterConfig)
+  }
+
+  const dir = skill.path ? dirname(skill.path) : skill.resolvedPath || process.cwd()
+
+  const output = [
+    `## Skill: ${skill.name}`,
+    "",
+    `**Base directory**: ${dir}`,
+    "",
+    body,
+  ]
+
+  if (mcpManager && getSessionID && skill.mcpConfig) {
+    const mcpInfo = await formatMcpCapabilities(
+      skill,
+      mcpManager,
+      getSessionID()
+    )
+    if (mcpInfo) {
+      output.push(mcpInfo)
+    }
+  }
+
+  return output.join("\n")
+}

src/tools/slashcommand/slashcommand-tool.ts

@@ -5,6 +5,7 @@ import { discoverCommandsSync } from "./command-discovery"
 import { buildDescriptionFromItems, TOOL_DESCRIPTION_PREFIX } from "./slashcommand-description"
 import { formatCommandList, formatLoadedCommand } from "./command-output-formatter"
 import { skillToCommandInfo } from "./skill-command-converter"
+import { formatSkillOutput } from "./skill-formatter"
 
 export function createSlashcommandTool(options: SlashcommandToolOptions = {}): ToolDefinition {
   let cachedCommands: CommandInfo[] | null = options.commands ?? null
@@ -75,6 +76,18 @@ export function createSlashcommandTool(options: SlashcommandToolOptions = {}): T
       )
 
       if (exactMatch) {
+        const skills = await getSkills()
+        const matchedSkill = skills.find(s => s.name === exactMatch.name)
+        
+        if (matchedSkill) {
+          return await formatSkillOutput(
+            matchedSkill,
+            options.mcpManager,
+            options.getSessionID,
+            options.gitMasterConfig
+          )
+        }
+        
         return await formatLoadedCommand(exactMatch, args.user_message)
       }
 

src/tools/slashcommand/types.ts

@@ -1,4 +1,6 @@
 import type { LoadedSkill, LazyContentLoader } from "../../features/opencode-skill-loader"
+import type { SkillMcpManager } from "../../features/skill-mcp-manager"
+import type { GitMasterConfig } from "../../config/schema/git-master"
 
 export type CommandScope = "builtin" | "config" | "user" | "project" | "opencode" | "opencode-project"
 
@@ -25,4 +27,10 @@ export interface SlashcommandToolOptions {
   commands?: CommandInfo[]
   /** Pre-loaded skills (skip discovery if provided) */
   skills?: LoadedSkill[]
+  /** MCP manager for skill MCP capabilities */
+  mcpManager?: SkillMcpManager
+  /** Function to get current session ID */
+  getSessionID?: () => string
+  /** Git master configuration */
+  gitMasterConfig?: GitMasterConfig
 }