Download

Use download_from_urls through Code Mode with run_sdk_snippet. Use the same tool for one or multiple files. It handles batch concurrency, progress, retries, transfer timeouts, partial files, and HTTP Range internally.

Normal Call

Usually pass only url and file_path:

from sdk.tool import tool

result = tool.call("download_from_urls", {
    "downloads": [
        {
            "url": "https://example.com/media/video.mp4",
            "file_path": "media/video.mp4",
        },
        {
            "url": "https://example.com/data/archive.zip",
            "file_path": "data/archive.zip",
        },
    ],
})
print(result.content)

Always check result.ok and read result.content. A batch may contain both successful and failed items, so keep the full summary.

Request Headers

Omit headers by default. The download engine automatically sends browser-compatible headers and a same-origin Referer. If a first request receives a likely source-validation rejection, it retries once with a same-origin Origin.

Provide headers only when the task already supplies a more accurate access context:

result = tool.call("download_from_urls", {
    "downloads": [{
        "url": "https://cdn.example.com/assets/report.pdf",
        "file_path": "reports/report.pdf",
        "headers": {
            "Referer": "https://www.example.com/reports/latest",
            "Origin": "https://www.example.com",
        },
    }],
})
print(result.content)

• Use a full page URL for Referer and only its scheme plus host for Origin.
• Pass Cookie or Authorization only when the user explicitly provided the value for this download.
• Never invent credentials or attempt to bypass login, CAPTCHA, WAF, DRM, or access controls.

Existing Files

overwrite defaults to true and is normally omitted. Set it to false only when the user wants to keep an existing complete target file.

If the requested destination may contain user-authored content and overwrite intent is unclear, call ask_user before starting Code Mode. ask_user cannot be called from inside a run_sdk_snippet script. Do not ask again when the user explicitly requested that destination or requested a replacement download.

Resume Behavior

On a recoverable failure, repeat the same url, file_path, and headers. The engine finds the preserved partial state and resumes automatically when the server supports HTTP Range. If the server does not safely support the saved range, the engine restarts that file without appending incompatible bytes.

Do not:

• read or pass internal .part or .part.meta paths;
• calculate offsets or send Range or If-Range;
• create resume tokens;
• pass download timeout, retry, concurrency, or chunk-size controls;
• change the destination path when the intent is to resume the same file.

When a failed item reports next action: retry_same_request, retry the unchanged item. If it reports review_request, inspect the URL, destination, or required access context before retrying.