map $http_user_agent $ai_crawler_block {
    default 0;

    "~*GPTBot" 1;
    "~*ChatGPT-User" 1;

    "~*ClaudeBot" 1;
    "~*Claude-Web" 1;
    "~*anthropic-ai" 1;

    "~*CCBot" 1;
    "~*Google-Extended" 1;
    "~*Applebot-Extended" 1;

    "~*FacebookBot" 1;
    "~*Meta-ExternalAgent" 1;

    "~*PerplexityBot" 1;
    "~*Bytespider" 1;
    "~*Diffbot" 1;
    "~*Amazonbot" 1;
    "~*cohere-ai" 1;
    "~*YouBot" 1;
    "~*Omgilibot" 1;
    "~*ImagesiftBot" 1;
    "~*FirecrawlAgent" 1;
}

client_body_buffer_size 10K;
client_header_buffer_size 1k;
large_client_header_buffers 2 1k;
server_tokens off;
more_clear_headers Server;
more_clear_headers X-Powered-By;