def add_request_headers(headers):
    """Add headers for 3rd party providers which we access data from."""

    # Pass our abuse policy in request headers for third-party site admins.
    headers["X-Abuse-Policy"] = "https://web.hypothes.is/abuse-policy/"
    headers["X-Complaints-To"] = "https://web.hypothes.is/report-abuse/"

    return headers