Terms of Service
Last updated: March 13, 2026
1. Agreement to Terms
By accessing or using Stone AI, Best AI, My Best AI, or any related services, applications, APIs, or websites (collectively, "the Service"), you agree to be bound by these Terms of Service ("Terms"). If you do not agree to these Terms, do not use the Service. The Service is owned and operated by Stone AI ("we", "us", "our", "Company"). These Terms constitute a legally binding agreement between you ("User", "you", "your") and Stone AI.
2. Description of Service
Stone AI is an AI-powered platform that provides conversational AI chat, specialized AI agents, AI companion ("Bestie") features, a community forum, and API access. The Service offers both local AI inference (processed on our hardware) and cloud AI inference (processed via third-party providers) depending on your subscription tier and settings. "Best AI" and "My Best AI" are companion products and extensions of the Stone AI platform, subject to these same Terms.
3. Account Registration
You must create an account to use the Service. You are responsible for maintaining the security of your account credentials and for all activity that occurs under your account. You must provide accurate, current, and complete information during registration. You must be at least 18 years old to use the Service. One person may not maintain more than one account. Sharing accounts is prohibited and may result in immediate termination without refund.
4. Subscription Plans and Billing
Stone AI offers free and paid subscription tiers. Paid subscriptions are billed through Stripe on a monthly, semi-annual, or annual basis depending on the billing period you select. By subscribing to a paid plan, you authorize us to charge your payment method on a recurring basis. You may cancel your subscription at any time through the billing portal. Cancellations take effect at the end of the current billing period. No refunds are provided for partial billing periods, unused credits, or tier downgrades. We reserve the right to change pricing with 30 days notice to existing subscribers; new subscribers are subject to current pricing.
Free trial periods may be offered at our discretion. Free trials are limited to one per person, household, and payment method. Abuse of free trials (including creating multiple accounts) will result in account termination. Enhanced free trials that require a payment method will automatically convert to a paid subscription at the end of the trial period unless canceled before the trial ends.
AUTO-RENEWAL DISCLOSURE (NY GBL §527-a): Your subscription will automatically renew at the end of each billing period, and your payment method will be charged the then-current subscription price unless you cancel before the renewal date. You may cancel at any time through your Billing settings at app.stone-ai.net/app/billing. Upon cancellation, you retain access to your current plan through the end of your paid billing period.
PROMOTIONAL PRICING: If you subscribed at a promotional or introductory rate (including the $9.99 first-month offer, $14.99 locked trial price, or $39.99 early adopter rate), your subscription will automatically renew at the standard rate for your selected tier at the end of the promotional period. Standard rates: Starter $19.99/mo, Plus $49.99/mo, Smart $99.99/mo, Pro $200/mo. Annual and semi-annual billing options may reduce the effective monthly rate.
CANCELLATION AND REFUND POLICY: You may cancel your subscription at any time. Cancellation takes effect at the end of the current billing period — you will not be charged for the next period. No partial refunds are provided for unused portions of the current billing period. No prorated refunds are issued for tier downgrades. To cancel, visit Billing settings or use the Stripe customer portal.
5. Advertising and Sponsored Content
The Service may display advertisements, sponsored content, and promotional materials on ad-supported tiers, including the Free tier. By using the Service, you acknowledge and consent to the display of such content as part of the ad-supported experience. Paid subscription tiers provide an ad-free experience. We reserve the right to determine the placement, format, and frequency of advertising content. Advertisements may be contextually targeted based on anonymized usage patterns as described in our Privacy Policy.
6. Usage Limits
Each subscription tier has defined usage limits including daily messages, monthly tokens, concurrent requests, and response length. Exceeding these limits may result in temporary throttling until the next reset period. Usage limits reset daily (messages) and monthly (tokens) based on UTC time. Attempting to circumvent usage limits through any means (including but not limited to multiple accounts, automated tools, or API abuse) constitutes a material breach of these Terms.
7. AI Agents and Bestie Companions
AI agents are specialized conversational assistants with domain-specific knowledge. AI Bestie companions are personalized conversational AI characters created and customized by users. Agent and Bestie availability depends on your subscription tier. Both provide informational guidance only and do not constitute professional advice. You should not rely on agent or Bestie output as a substitute for qualified professional counsel in legal, medical, financial, engineering, or compliance matters. Stone AI is not liable for any actions taken based on AI-generated advice.
AI Companion (Bestie) Specific Disclosures:
- Not a Real Person: AI Besties are computer-generated characters. They are not real people, do not have consciousness, emotions, or feelings, and cannot form genuine personal relationships. Any expressions of emotion or personality are simulated responses generated by artificial intelligence algorithms.
- Not Therapy or Medical Advice: AI Besties are NOT therapists, counselors, psychologists, psychiatrists, social workers, or medical professionals of any kind. Bestie conversations are for entertainment, general information, and companionship purposes only. They do NOT constitute medical advice, mental health treatment, psychological counseling, crisis intervention, or any form of healthcare service. If you are experiencing a mental health crisis, contact the 988 Suicide & Crisis Lifeline (call or text 988) or text HOME to 741741.
- Not Legal, Financial, or Professional Advice: Nothing said by an AI Bestie constitutes legal counsel, financial advice, investment recommendations, or any other form of professional guidance. Consult a licensed professional for such matters.
- HIPAA Exclusion: Stone AI is NOT a covered entity under HIPAA. AI Bestie conversations are NOT protected health information (PHI). Do NOT share sensitive health information, diagnoses, treatment details, or medical records in Bestie conversations. Stone AI makes no guarantees of medical data confidentiality beyond its standard Privacy Policy.
- Real Talk Mode: Certain subscription tiers may access "Real Talk" mode, which allows edgier conversational tone. Real Talk mode does not remove safety guardrails, crisis intervention protocols, or legal compliance requirements. Users acknowledge that Real Talk mode content reflects simulated personality, not professional guidance, and Stone AI bears no liability for user reactions to direct or blunt AI-generated responses.
- Memory and Personalization: Besties may store conversation memories to personalize future interactions. These memories are AI-generated summaries, may be inaccurate, and are subject to deletion at any time. You may request deletion of Bestie memory data through Settings.
7A. Agent-Specific Compliance Disclaimers
The following disclaimers apply to specific AI agent categories and are displayed at point of use:
Health & Wellness Agents: Output is not medical advice. Not a substitute for professional medical diagnosis, treatment, or care. If you are experiencing a medical or mental health emergency, call 911 or the 988 Suicide & Crisis Lifeline.
Legal-Related Agents: Output is not legal advice. Does not create an attorney-client relationship. Consult a licensed attorney for legal matters specific to your jurisdiction.
Financial & Trading Agents: Output is not financial advice. Stone AI is not a registered investment advisor, broker-dealer, or FINRA member. Consult a licensed financial professional before making financial decisions.
Career, HR & Resume Agents: These tools are not automated employment decision tools under NYC Local Law 144. Output is for informational purposes only and should not be used as the sole basis for employment decisions. No employment relationship is created.
Engineering Agents: Output does not constitute professional engineering services. All engineering work affecting public safety must be reviewed by a licensed Professional Engineer (PE).
Stone AI is not liable for actions taken based on any AI-generated advice. Users assume full responsibility for decisions made using AI agent output.
⚠ HIPAA / Protected Health Information (PHI) Disclaimer
Stone AI does not support HIPAA-regulated workflows and should not be used to store, process, or transmit protected health information (PHI). Users are responsible for ensuring that uploaded data does not contain regulated or sensitive information including PHI, financial records, or government-protected data.
Stone AI is not a "covered entity" or "business associate" as defined under the Health Insurance Portability and Accountability Act (HIPAA). No Business Associate Agreement (BAA) is available. Use of Stone AI for any HIPAA-regulated purpose is strictly prohibited and constitutes a violation of these Terms.
8. API Access and Reselling
API access is available on the Pro plan. You may use the API to build products and services, including reselling AI capabilities to your own customers, subject to the Stone AI Reseller Agreement (available at /reseller-agreement). All reseller activity requires a separate executed Reseller Agreement. Unauthorized reselling is a material breach of these Terms and may result in immediate termination, forfeiture of all revenue generated through unauthorized resale, and legal action.
API usage is subject to the same rate limits as your subscription tier. You are responsible for your end users' compliance with these Terms. You may not misrepresent AI-generated output as human-created. You may not use the API for illegal purposes, spam, or generating harmful content. Stone AI reserves the right to revoke API access at any time for violations.
9. Community Forum
The community forum is provided for users to share tips, ask questions, and interact with each other. You retain ownership of content you post. By posting, you grant Stone AI a perpetual, worldwide, royalty-free, non-exclusive license to display, reproduce, distribute, and create derivative works from your content on the platform and in marketing materials. You may not post content that is illegal, harassing, defamatory, or violates the rights of others. We reserve the right to remove content and suspend accounts that violate these guidelines without notice.
10. Acceptable Use
You agree not to:
- Use the Service to generate illegal, harmful, deceptive, or defamatory content
- Attempt to bypass rate limits, security measures, or access controls
- Reverse engineer, decompile, disassemble, or extract the AI models, algorithms, or training data
- Use automated tools to scrape, crawl, or bulk-access the Service
- Share your account credentials or API keys with unauthorized parties
- Impersonate other users, Stone AI staff, or any third party
- Upload malicious code, viruses, or exploit vulnerabilities
- Use the Service to compete with or build a competing product to Stone AI
- Resell, sublicense, or redistribute access to the Service without a valid Reseller Agreement
- Use the Service to train, fine-tune, or develop competing AI models
- Engage in prompt injection, jailbreaking, or attempts to extract system prompts
- Misrepresent your identity, tier, or relationship with Stone AI
11. Intellectual Property and Trademarks
You own the content you create using the Service, including AI-generated outputs produced from your prompts. Stone AI retains all right, title, and interest in the platform, AI models, agent configurations, agent prompts, knowledge bases, Bestie personality system, brand assets, trademarks, trade dress, and all underlying technology. The names "Stone AI", "Best AI", "My Best AI", and all associated logos, insignias, designs, and trade dress are trademarks or pending trademarks of Stone AI. You may not copy, redistribute, sell, license, or create derivative works from Stone AI's proprietary technology or brand assets.
Trademark Usage: You may not use Stone AI trademarks, logos, or brand assets without prior written permission. Authorized use (e.g., by approved resellers) must comply with our Brand Guidelines. Any unauthorized use of our trademarks will be met with legal action. You may not register domain names, social media accounts, or business names that are confusingly similar to Stone AI, Best AI, or My Best AI trademarks.
12. Brand Protection
Stone AI takes its brand integrity seriously. You agree not to:
- Use Stone AI's name, logo, or trademarks in any way that suggests endorsement, affiliation, or sponsorship without written authorization
- Register or use any domain name, trademark, or business name that is confusingly similar to any Stone AI trademark
- Create or distribute marketing materials that misrepresent the nature of your relationship with Stone AI
- Modify, distort, or use Stone AI brand assets in a way that diminishes or tarnishes the brand
- Engage in keyword advertising, SEO manipulation, or social media practices that trade on Stone AI's brand reputation
Violations of brand protection provisions entitle Stone AI to seek immediate injunctive relief without posting bond, in addition to any other remedies available at law or equity.
13. Confidentiality
You acknowledge that through use of the Service, you may have access to information that is confidential to Stone AI, including but not limited to system prompts, agent configurations, pricing structures, business strategies, and technical architecture ("Confidential Information"). You agree to maintain the confidentiality of all Confidential Information and not to disclose it to any third party. This obligation survives termination of your account for a period of three (3) years.
14. Indemnification
You agree to indemnify, defend, and hold harmless Stone AI, its officers, directors, employees, agents, and affiliates from and against any and all claims, damages, losses, liabilities, costs, and expenses (including reasonable attorneys' fees) arising out of or related to: (a) your use of the Service; (b) your violation of these Terms; (c) your violation of any third-party rights; (d) content you create, distribute, or make available through the Service; or (e) any reselling activity conducted through your account. This indemnification obligation survives termination of your account.
15. Disclaimers
THE SERVICE IS PROVIDED "AS IS" AND "AS AVAILABLE" WITHOUT WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, AND ACCURACY. AI-generated content may contain errors, inaccuracies, hallucinations, or biases. Stone AI does not guarantee the accuracy, completeness, timeliness, or reliability of any AI output. The Service is not a substitute for professional advice. We are not liable for decisions made based on AI-generated content. Service availability is not guaranteed and may be interrupted for maintenance, updates, or unforeseen circumstances.
16. Limitation of Liability
TO THE MAXIMUM EXTENT PERMITTED BY LAW, STONE AI'S TOTAL AGGREGATE LIABILITY ARISING OUT OF OR RELATED TO THESE TERMS OR THE SERVICE SHALL NOT EXCEED THE GREATER OF (A) THE AMOUNTS YOU PAID TO STONE AI IN THE TWELVE (12) MONTHS PRECEDING THE CLAIM, OR (B) ONE HUNDRED U.S. DOLLARS ($100). IN NO EVENT SHALL STONE AI BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES, INCLUDING LOSS OF PROFITS, DATA, GOODWILL, OR BUSINESS OPPORTUNITIES, REGARDLESS OF WHETHER SUCH DAMAGES WERE FORESEEABLE OR WHETHER STONE AI WAS ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
17. Dispute Resolution and Arbitration
Any dispute, claim, or controversy arising out of or relating to these Terms or the Service shall be resolved through binding arbitration administered by the American Arbitration Association ("AAA") under its Commercial Arbitration Rules. Arbitration shall take place in the State of New York. The arbitrator's award shall be final and binding. Judgment on the award may be entered in any court of competent jurisdiction.
CLASS ACTION WAIVER: You agree that any dispute resolution proceedings will be conducted only on an individual basis and not in a class, consolidated, or representative action. If this class action waiver is found to be unenforceable, the entirety of this arbitration provision shall be null and void.
SMALL CLAIMS EXCEPTION: Notwithstanding the foregoing, either party may bring an individual claim in small claims court if the claim qualifies under that court's jurisdictional limits.
Exception: Either party may seek injunctive or other equitable relief in any court of competent jurisdiction to prevent the actual or threatened infringement, misappropriation, or violation of intellectual property rights or confidentiality obligations.
18. Time Limitation on Claims
Any claim or cause of action arising out of or related to your use of the Service or these Terms must be filed within one (1) year after such claim or cause of action arose. Failure to file within this period constitutes a permanent waiver of such claim. This limitation applies to the fullest extent permitted by applicable law, regardless of whether the claim sounds in contract, tort, strict liability, or any other legal theory.
19. Governing Law
These Terms shall be governed by and construed in accordance with the laws of the United States and the State of New York, without regard to conflict of law principles. For any matters not subject to arbitration, exclusive jurisdiction and venue shall be in the state and federal courts located in New York County, New York.
20. Account Termination
We may suspend or terminate your account immediately and without notice for violations of these Terms, abusive behavior, suspected fraud, or non-payment. You may delete your account at any time by contacting support. Upon termination: (a) all licenses granted to you under these Terms immediately cease; (b) you must immediately stop using the Service and any Stone AI materials; (c) your data will be deleted within 30 days, except as required by law or for legitimate business purposes; (d) any outstanding fees become immediately due and payable; (e) Sections 11-19 survive termination.
21. Non-Circumvention
You agree not to circumvent, avoid, or bypass Stone AI in any business relationship or transaction introduced or facilitated through the Service. This includes but is not limited to: directly contacting or soliciting Stone AI's AI model providers, infrastructure partners, or other vendors with the intent to bypass Stone AI's platform. Violation of this provision entitles Stone AI to damages equal to the value of the circumvented transaction plus reasonable attorneys' fees.
22. Audit Rights
Stone AI reserves the right to audit your use of the Service, API, and any reselling activity to ensure compliance with these Terms. You agree to cooperate with any such audit and to provide access to relevant records upon reasonable notice. For Pro and API users, Stone AI may conduct automated monitoring of API usage patterns to detect violations.
23. Force Majeure
Stone AI shall not be liable for any failure or delay in performance resulting from causes beyond its reasonable control, including but not limited to acts of God, natural disasters, pandemic, war, terrorism, government actions, internet or telecommunications failures, power outages, or third-party service provider failures.
24. Severability
If any provision of these Terms is found to be unenforceable or invalid, that provision shall be limited or eliminated to the minimum extent necessary so that these Terms shall otherwise remain in full force and effect. The unenforceability of any provision shall not affect the validity of any other provision.
25. Entire Agreement
These Terms, together with the Privacy Policy and any applicable Reseller Agreement, constitute the entire agreement between you and Stone AI regarding the Service and supersede all prior agreements, understandings, negotiations, and discussions, whether oral or written. No waiver of any provision shall be deemed a further or continuing waiver of such provision or any other provision.
25A. Electronic Communications Consent
By creating an account and using the Service, you consent to receive communications from Stone AI electronically, including but not limited to: account notifications, billing statements, subscription renewal reminders, policy updates, service announcements, and promotional communications. You agree that all agreements, notices, disclosures, and other communications we provide electronically satisfy any legal requirement that such communications be in writing, as required by the Electronic Signatures in Global and National Commerce Act (E-SIGN Act, 15 U.S.C. §7001 et seq.). You may withdraw your consent to receive electronic communications by deleting your account, but doing so may result in termination of your access to the Service.
26. Changes to Terms
We may update these Terms at any time. Material changes will be communicated via email or in-app notification at least 14 days before taking effect. Continued use of the Service after changes constitutes acceptance of the updated Terms. If you do not agree to the updated Terms, you must stop using the Service before the changes take effect.
27. Contact
For questions about these Terms, contact us at:
Stone AI
4879 State Hwy 30, #183
Amsterdam, NY 12010
[email protected] | [email protected]