Function execute

packages/arctic/src/tool/webfetch.ts:21–142

(params, ctx)

    timeout: z.number().describe("Optional timeout in seconds (max 120)").optional(),
  }),
  async execute(params, ctx) {
    // Validate URL
    if (!params.url.startsWith("http://") && !params.url.startsWith("https://")) {
      throw new Error("URL must start with http:// or https://")
    }

    const cfg = await Config.get()
    if (cfg.permission?.webfetch === "ask")
      await Permission.ask({
        type: "webfetch",
        sessionID: ctx.sessionID,
        messageID: ctx.messageID,
        callID: ctx.callID,
        title: "Fetch content from: " + params.url,
        metadata: {
          url: params.url,
          format: params.format,
          timeout: params.timeout,
        },
      })

    const timeout = Math.min((params.timeout ?? DEFAULT_TIMEOUT / 1000) * 1000, MAX_TIMEOUT)

    const controller = new AbortController()
    const timeoutId = setTimeout(() => controller.abort(), timeout)

    // Build Accept header based on requested format with q parameters for fallbacks
    let acceptHeader = "*/*"
    switch (params.format) {
      case "markdown":
        acceptHeader = "text/markdown;q=1.0, text/x-markdown;q=0.9, text/plain;q=0.8, text/html;q=0.7, */*;q=0.1"
        break
      case "text":
        acceptHeader = "text/plain;q=1.0, text/markdown;q=0.9, text/html;q=0.8, */*;q=0.1"
        break
      case "html":
        acceptHeader = "text/html;q=1.0, application/xhtml+xml;q=0.9, text/plain;q=0.8, text/markdown;q=0.7, */*;q=0.1"
        break
      default:
        acceptHeader =
          "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8"
    }

    const response = await fetch(params.url, {
      signal: AbortSignal.any([controller.signal, ctx.abort]),
      headers: {
        "User-Agent":
          "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36",
        Accept: acceptHeader,
        "Accept-Language": "en-US,en;q=0.9",
      },
    })

    clearTimeout(timeoutId)

    if (!response.ok) {
      throw new Error(`Request failed with status code: ${response.status}`)
    }