tool updates

packages/opencode/src/tool/webfetch.ts

@@ -0,0 +1,104 @@
+import { z } from "zod"
+import { Tool } from "./tool"
+import TurndownService from "turndown"
+import DESCRIPTION from "./webfetch.txt"
+
+const MAX_RESPONSE_SIZE = 5 * 1024 * 1024 // 5MB
+const DEFAULT_TIMEOUT = 30 * 1000 // 30 seconds
+const MAX_TIMEOUT = 120 * 1000 // 2 minutes
+
+export const WebFetchTool = Tool.define({
+  id: "opencode.webfetch",
+  description: DESCRIPTION,
+  parameters: z.object({
+    url: z.string().describe("The URL to fetch content from"),
+    format: z
+      .enum(["text", "markdown", "html"])
+      .describe(
+        "The format to return the content in (text, markdown, or html)",
+      ),
+    timeout: z
+      .number()
+      .min(0)
+      .max(MAX_TIMEOUT / 1000)
+      .describe("Optional timeout in seconds (max 120)")
+      .optional(),
+  }),
+  async execute(params) {
+    // Validate URL
+    if (
+      !params.url.startsWith("http://") &&
+      !params.url.startsWith("https://")
+    ) {
+      throw new Error("URL must start with http:// or https://")
+    }
+
+    const timeout = Math.min(
+      (params.timeout ?? DEFAULT_TIMEOUT / 1000) * 1000,
+      MAX_TIMEOUT,
+    )
+
+    const controller = new AbortController()
+    const timeoutId = setTimeout(() => controller.abort(), timeout)
+
+    const response = await fetch(params.url, {
+      signal: controller.signal,
+      headers: {
+        "User-Agent": "opencode/1.0",
+      },
+    })
+
+    clearTimeout(timeoutId)
+
+    if (!response.ok) {
+      throw new Error(`Request failed with status code: ${response.status}`)
+    }
+
+    // Check content length
+    const contentLength = response.headers.get("content-length")
+    if (contentLength && parseInt(contentLength) > MAX_RESPONSE_SIZE) {
+      throw new Error("Response too large (exceeds 5MB limit)")
+    }
+
+    const arrayBuffer = await response.arrayBuffer()
+    if (arrayBuffer.byteLength > MAX_RESPONSE_SIZE) {
+      throw new Error("Response too large (exceeds 5MB limit)")
+    }
+
+    const content = new TextDecoder().decode(arrayBuffer)
+    const contentType = response.headers.get("content-type") || ""
+
+    switch (params.format) {
+      case "text":
+        if (contentType.includes("text/html")) {
+          const text = extractTextFromHTML(content)
+          return { output: text, metadata: {} }
+        }
+        return { output: content, metadata: {} }
+
+      case "markdown":
+        if (contentType.includes("text/html")) {
+          const markdown = convertHTMLToMarkdown(content)
+          return { output: markdown, metadata: {} }
+        }
+        return { output: "```\n" + content + "\n```", metadata: {} }
+
+      case "html":
+        return { output: content, metadata: {} }
+
+      default:
+        return { output: content, metadata: {} }
+    }
+  },
+})
+
+function extractTextFromHTML(html: string): string {
+  const doc = new DOMParser().parseFromString(html, "text/html")
+  const text = doc.body.textContent || doc.body.innerText || ""
+  return text.replace(/\s+/g, " ").trim()
+}
+
+function convertHTMLToMarkdown(html: string): string {
+  const turndownService = new TurndownService()
+  return turndownService.turndown(html)
+}