Privacy Policy

Effective date: August 10, 2026

This Privacy Policy explains how YiAPI, operated by ArcStack LLC, collects, uses, stores, and protects personal information, service content, and payment-related data.

Information We Collect

We may collect account information such as email address, login identifiers, authentication status, user ID, API key metadata, order records, subscription records, support messages, and service usage records.

When you make a payment, payment details are processed by our payment providers, including Stripe where available. We receive payment status, transaction identifiers, order metadata, billing amount, currency, and refund status. We do not store full card numbers.

We may also collect technical information such as IP address, browser type, device information, request logs, error logs, security events, and cookies or similar local storage needed for login, security, preferences, and service operation.

We collect the content of all requests sent through the service and their corresponding responses, including prompts, instructions, inputs, attachments, generated outputs, and associated metadata.

How We Use Information

We use information to provide the service, authenticate users, process payments, deliver subscriptions or balance credits, prevent fraud and abuse, enforce service rules, provide support, maintain security, analyze reliability, and comply with legal obligations.

We may use request and response content to develop, train, fine-tune, evaluate, test, and improve artificial intelligence and machine learning models.

Sharing and Processors

We share information with service providers only as needed to operate the service, including hosting providers, analytics or monitoring tools, email delivery services, authentication providers, and payment processors such as Stripe. These providers process data under their own security and privacy obligations.

We may also disclose or provide request and response content to our partners. We and those partners may use that content to develop, train, fine-tune, evaluate, test, and improve artificial intelligence and machine learning models.

Data Retention

We retain account, order, payment status, usage, and security records for as long as needed to provide the service, resolve disputes, comply with accounting or legal requirements, and protect against fraud or abuse.

We may retain request and response content for as long as reasonably needed for the model development, training, evaluation, testing, and improvement purposes described above, including after account closure where permitted by law. Content provided to our partners is also subject to their retention practices and legal obligations.

Security

We use reasonable administrative, technical, and organizational safeguards to protect personal information. No online service can guarantee absolute security, so you should keep your password and API keys confidential.

Your Choices

You may access or update certain account information in your dashboard. You may contact us to request access, correction, deletion, or other privacy-related assistance, subject to legal, security, and operational limitations.

International Users

If you access the service from outside the United States, your information may be processed in the United States or other locations where our service providers operate.

Contact

For privacy questions, contact us at contact@arcstack.cc.