CapMonster Cloud Rust SDK: AI Captcha Solver & Anti-Bot Bypass

Official asynchronous Rust SDK for CapMonster Cloud. Plug ultra-fast AI captcha recognition into your tokio based scrapers and browser-automation workflows (fantoccini, thirtyfour, chromiumoxide, reqwest, ...) without human-in-the-loop delays.

👉 Get your Free API Key & Free Trial Balance on CapMonster Cloud

⚡ Highlights & Benchmarks

• ⚡ Sub-Second Speed: Automated AI models solve captchas in 300 ms to 6 seconds depending on the system load.
• 🤖 Zero Human Workers: 100% automated machine learning pipeline with no manual latencies.
• 🦀 Type-Safe Requests: required parameters are constructor arguments, closed value sets are enums, inconsistent requests are rejected locally before anything is sent.
• 🛡️ Modern Anti-Bot Bypass: Full support for Cloudflare Turnstile, reCAPTCHA Enterprise, GeeTest, DataDome and Amazon WAF.
• 💰 Cost-Effective: Low-cost pricing structure based on pay-as-you-go balance.

📦 Installation

[dependencies]
capmonstercloud-client = "0.1"
tokio = { version = "1", features = ["macros", "rt-multi-thread"] }

Minimum supported Rust version: 1.88. TLS is rustls (no OpenSSL needed).

🚀 Quick Start & Usage Examples

1. Asynchronous reCAPTCHA v2 Solving

use capmonstercloud_client::requests::RecaptchaV2Request;
use capmonstercloud_client::{CapMonsterClient, ClientOptions};

#[tokio::main]
async fn main() -> capmonstercloud_client::Result<()> {
    // Initialize client with your API key from the dashboard
    let client = CapMonsterClient::new(ClientOptions::new("YOUR_CAPMONSTER_API_KEY"))?;

    // Build the task payload
    let request = RecaptchaV2Request::new(
        "https://lessons.zennolab.com/captchas/recaptcha/v2_simple.php?level=high",
        "6Lcg7CMUAAAAANphynKgn9YAgA4tQ2KI_iqRyTwd",
    );

    // Send task and receive token (the `solution` object as serde_json::Value)
    let solution = client.solve_captcha(&request).await?;
    println!("reCAPTCHA Token: {}", solution["gRecaptchaResponse"]);
    Ok(())
}

2. Cloudflare Turnstile with a proxy

use capmonstercloud_client::requests::{TurnstileRequest, TurnstileStandard};
use capmonstercloud_client::{CapMonsterClient, ClientOptions, ProxyInfo, ProxyType};

#[tokio::main]
async fn main() -> capmonstercloud_client::Result<()> {
    let client = CapMonsterClient::new(ClientOptions::new("YOUR_CAPMONSTER_API_KEY"))?;

    let proxy = ProxyInfo::new(ProxyType::Http, "203.0.113.10", 8080).with_auth("login", "password");
    let request = TurnstileRequest::new(
        "https://target-website.com/login",
        "0x4AAAAAAABnPIDnK2k_e-2",
        TurnstileStandard::new().with_proxy(proxy),
    );

    let solution = client.solve_captcha(&request).await?;
    // inject solution["token"] into the cf-turnstile-response field of your browser session and submit
    println!("Turnstile token: {}", solution["token"]);
    Ok(())
}

3. Account balance and low-level calls

println!("balance: {}", client.get_balance().await?);

// solve_captcha() = create_task() + polling get_task_result()
let task_id = client.create_task(&request).await?;
match client.get_task_result(task_id).await? {
    TaskStatus::Processing => println!("not ready yet"),
    TaskStatus::Ready(solution) => println!("{solution}"),
}

ClientOptions knobs: with_service_url, with_soft_id (default 152), with_client_timeout (one HTTP request, default 20 s), with_client_proxy (http/https proxy for the SDK's own requests), with_timeouts_override. Errors are a single capmonstercloud_client::Error enum (Validation, Http, CreateTask, GetResult, Timeout, ...).

🛡️ Supported CAPTCHA Types

All task types conform to the official CapMonster Cloud API Documentation:

One source file per type lives in src/requests/.

🛠️ How It Works

[ Your service ]
         │
         ▼
[ Extract sitekey & website URL ]
         │
         ▼
[ CapMonsterClient ] ──► POST createTask to https://api.capmonster.cloud
         │
         ▼
[ Neural Network Processing ] ──► Poll getTaskResult (300ms - 6s)
         │
         ▼
[ Receive Token & Autosubmit ] ──► Complete bypass

⚙️ Best Practices

• Token Expiration: Most tokens (reCAPTCHA, Turnstile) remain valid for 120 seconds. Inject and submit the solution immediately after receiving the response.
• Proxy Usage: For custom tasks and strict protections, use the same proxy in your scraping session and the CapMonster task payload.
• Balance Monitoring: Ensure your account balance remains positive in the Dashboard.
• Secrets in logs: Debug output of ClientOptions and proxies masks the API key and passwords.

🏷️ Versioning & releases

The crate follows SemVer; user-visible changes are listed in CHANGELOG.md. While the major version is 0:

Release flow (automated by .github/workflows/release.yml): in a PR bump version in Cargo.toml and add a ## [X.Y.Z] section to CHANGELOG.md; after the merge to main the workflow publishes to crates.io, tags vX.Y.Z and creates a GitHub Release. The version is also sent in the User-Agent of every request (Zennolab.CapMonsterCloud.Client.Rust/X.Y.Z).

🧩 Adding a captcha type

1. src/requests/<snake_name>.rs: a #[derive(Serialize)] struct with new() + with_* setters, impl CaptchaRequest (TASK_TYPE, CLASS for CustomTask, timeouts(), optional validate()) and a test asserting the exact JSON. Copy recaptcha_v2.rs (plain task) or altcha.rs (CustomTask with typed metadata).
2. Register it in src/requests/mod.rs (mod + pub use). Nothing else: the client is generic over CaptchaRequest.
3. cargo fmt && cargo clippy --all-targets -- -D warnings && cargo test (unit tests and the mocked-API tests need neither network nor API key).

📚 Official Documentation & Links

• 📖 Getting Started Guide
• 🎯 Supported Captchas Overview
• ⚙️ API Methods Reference
• 💬 Support & Community

📄 License

MIT © ZennoLab / CapMonster Cloud