feat(tool): add tool_search for dynamic tool discovery

packages/opencode/src/tool/registry.ts

@@ -26,6 +26,7 @@ import { Log } from "@/util/log"
 import { LspTool } from "./lsp"
 import { Truncate } from "./truncation"
 import { PlanExitTool, PlanEnterTool } from "./plan"
+import { ToolSearchTool } from "./tool-search"
 
 export namespace ToolRegistry {
   const log = Log.create({ service: "tool.registry" })
@@ -108,6 +109,7 @@ export namespace ToolRegistry {
       WebSearchTool,
       CodeSearchTool,
       SkillTool,
+      ToolSearchTool,
       ...(Flag.OPENCODE_EXPERIMENTAL_LSP_TOOL ? [LspTool] : []),
       ...(config.experimental?.batch_tool === true ? [BatchTool] : []),
       ...(Flag.OPENCODE_EXPERIMENTAL_PLAN_MODE && Flag.OPENCODE_CLIENT === "cli" ? [PlanExitTool, PlanEnterTool] : []),

packages/opencode/src/tool/tool-search.ts

@@ -0,0 +1,45 @@
+import z from "zod"
+import { Tool } from "./tool"
+import { ToolRegistry } from "./registry"
+
+export const ToolSearchTool = Tool.define("tool_search", {
+  description: `Search for available tools by name or description.
+Use this when you need to find a tool for a specific task.
+Returns a list of matching tool names that you can then use.`,
+  parameters: z.object({
+    query: z.string().describe("Regex pattern to search tool names and descriptions"),
+  }),
+  async execute(params, ctx) {
+    const tools = await ToolRegistry.tools("", ctx.extra?.agent)
+    const regex = new RegExp(params.query, "i")
+
+    const matches: { id: string; description: string }[] = []
+    for (const tool of tools) {
+      if (tool.id === "tool_search" || tool.id === "invalid") continue
+      if (regex.test(tool.id) || regex.test(tool.description)) {
+        matches.push({
+          id: tool.id,
+          description: tool.description.slice(0, 100),
+        })
+      }
+    }
+
+    if (matches.length === 0) {
+      return {
+        title: "No tools found",
+        metadata: { matches: 0 },
+        output: `No tools found matching "${params.query}"`,
+      }
+    }
+
+    const output = matches
+      .map((m) => `- ${m.id}: ${m.description}`)
+      .join("\n")
+
+    return {
+      title: `Found ${matches.length} tools`,
+      metadata: { matches: matches.length, tools: matches.map((m) => m.id) },
+      output: `Found ${matches.length} tool(s) matching "${params.query}":\n${output}`,
+    }
+  },
+})