Terms of Service

Last updated: 6 October 2026 · Draft pending legal review

These Terms of Service ("Terms") are the agreement between you and Spawncore Unipessoal Lda ("Spawncore", "we", "us") for the use of Probator.ai, its website, editor, apps and API (together, the "Service"). Please read them carefully. By creating an account, subscribing or using the Service, you accept these Terms.

1. Who we are

The Service is provided by Spawncore Unipessoal Lda, a private limited company registered in Portugal with tax number (NIPC) [NIPC], registered office at [REGISTERED ADDRESS], registered with the Commercial Registry of [REGISTRY], share capital [SHARE CAPITAL]. You can reach us at legal@probator.ai. Full company details are in our Legal Notice.

2. What the Service does

Probator.ai analyses text and documents that you provide and returns:

• Grammar and style suggestions for spelling, grammar, punctuation, clarity, word choice and style;
• AI-detection results: an estimate of how likely a text, and each sentence in it, is to have been generated or heavily edited by an artificial-intelligence system, produced by our own detection model combined with other signals;
• Plagiarism results: passages that match other sources, such as our own index, the public web, academic databases and, if you choose, your own comparison library;
• Hidden-mark analysis: invisible characters, look-alike letters, concealed text and file metadata;
• Document storage in your account and a programming interface (API) on eligible plans.

How the AI features work, what they can and cannot do, and how you must use them are described in our AI Policy, which forms part of these Terms.

3. Results are probabilities, not proof

AI-detection and plagiarism results are statistical estimates. They can be wrong in both directions: human writing can be flagged as AI-generated (for example formal, technical, translated or non-native writing), and AI-generated text can go undetected. Matches with other sources may be legitimate quotations or common phrases.

You must not use a result from the Service as the sole basis for a decision that affects a person, such as an academic sanction, a grade, a hiring or employment decision, or an accusation of misconduct. Any such decision must involve meaningful human review of the full context, and the person concerned should be given the opportunity to explain. Grammar suggestions may also be wrong; you decide whether to accept them.

4. Accounts and sign-in

• You may try parts of the Service without an account, within a small daily allowance. Saving documents, larger checks, paid plans and the API require an account.
• You sign in with a one-time code sent to your email address, or with a passkey. You are responsible for keeping access to your email account and devices secure, and for all activity in your account.
• You must give a valid email address you control. One person may not create several free accounts to obtain more free credits.
• You must be at least 16 years old to create an account. If you are between 13 and 16, you may use the Service only with the consent of a parent or legal guardian, or through an account provided by your school or another institution that is responsible for obtaining that consent.
• If you use the Service on behalf of an organisation, you confirm that you are authorised to accept these Terms for it, and "you" includes that organisation.

5. Plans, credits and storage

The Service is offered on a Free plan and on paid plans (currently Starter, Pro and Team). The features, monthly credit allowance, storage limit and price of each plan are shown on our pricing page and in your account at the time you subscribe.

• Credits. Checks consume credits from a monthly pool: AI detection uses 1 credit per word, grammar 1 credit per 3 words, plagiarism 2 credits per word, and a deep scan adds 1,500 credits. The editor shows the estimated cost before you run a check. A check that fails on our side is not charged. Identical checks repeated within a short period may be served from cache at no cost.
• Monthly reset. Unused monthly credits do not roll over. Yearly plans receive their monthly allowance each month of the year.
• Top-ups. Credits bought as a one-off top-up do not expire while your account exists and are used after your monthly pool.
• Storage. Saved documents count towards your plan's storage limit (currently 50 MB on the Free plan and 1 GB on paid plans), including the original file, the extracted text and the latest report. If you exceed the limit, for example after downgrading, you cannot save new documents until you free up space; we will not delete your existing documents for that reason without giving you at least 30 days' notice.
• Fair use. We may set technical limits (such as words per check, file size and requests per minute) to keep the Service reliable. Current limits are shown in the editor and the API documentation.

6. Prices, payment and taxes

• Payments are processed by Stripe. We do not see or store your full card details.
• Prices for consumers in the European Union include VAT at the rate applicable in your country. Prices for business customers exclude VAT, which is charged or reverse-charged according to the law. Payments are processed by Stripe; invoices are issued by Spawncore Unipessoal Lda with invoicing software certified by the Portuguese Tax Authority and are available to download in your account.
• Subscriptions renew automatically at the end of each billing period (monthly or yearly) until you cancel. We charge the payment method on file at each renewal.
• We may change our prices for future periods. We will tell you at least 30 days before a price change affects your subscription, and you may cancel before it takes effect.
• If a payment fails, we may retry it and limit your account to the Free plan's features until the payment succeeds.

7. Cancellation, right of withdrawal and refunds

Cancelling. You can cancel a subscription at any time from your account (Manage billing). Cancellation takes effect at the end of the current billing period; you keep paid features until then. We do not refund unused time in a period, except as required by law or stated below.

Right of withdrawal (consumers in the EU). If you are a consumer, you have the right to withdraw from a subscription or top-up purchase within 14 days of the purchase without giving a reason. When you subscribe, you ask us to start providing the Service immediately. If you withdraw, we refund the amount you paid, minus an amount proportional to the Service already provided, which we calculate from the credits you used out of the credits included. If you used all the included credits, the Service has been fully provided and the right of withdrawal no longer applies. To withdraw, send a clear statement to legal@probator.ai, for example using the model form in the Annex. We refund you within 14 days of receiving your request, using the same payment method.

Faults. If the Service does not conform to these Terms, you have the rights given to you by law, including to have it brought into conformity or, where that is not possible, to a price reduction or to terminate the contract.

8. Your content

• You own your content. Texts, documents and other material you submit ("Your Content") remain yours. We claim no ownership of Your Content or of the results generated for you.
• Licence to us. You give us a limited, non-exclusive, worldwide licence to host, copy, process and transmit Your Content only as needed to provide the Service to you, including sending excerpts to the service providers listed in our sub-processor list (for example, short phrases to a web-search provider during a plagiarism check). This licence ends when Your Content is deleted from our systems.
• No training on your content. We do not use Your Content to train or improve our models or anyone else's, and we instruct our language-model providers not to store or train on it.
• Comparison library. If you choose to add a document to your comparison library, we store hashed fingerprints derived from it so that future checks in your account can detect matches with it. You can remove library entries by deleting your account data.
• Your responsibility. You confirm that you have the right to submit Your Content and that doing so does not infringe anyone's rights or the law. If Your Content contains personal data about other people (for example, essays by students or CVs from candidates), you are responsible for having a lawful basis to process it and for informing those people as required. Business customers who process such data with us can rely on our Data Processing Agreement.

9. Acceptable use

You must not, and must not help anyone else to:

• use the Service in breach of the law or of anyone's rights, including privacy, data-protection and intellectual-property rights;
• use results as the sole basis for decisions about people, or present results or certificates as definitive proof (see sections 3 and 11 and our AI Policy);
• use the Service to systematically develop, test or tune methods for evading AI detection or plagiarism detection, or to build a competing detector from our outputs;
• remove, alter or obscure machine-readable marks that identify content as generated or manipulated by AI (such as watermarks, Content Credentials or AI labels), or use the Service to help anyone else do so. The Service reports such marks and is designed not to remove them;
• use a disclosure label or a human review record that you know to be untrue, or present a certificate as a disclosure that a text was not generated by AI;
• submit malware, or attempt to probe, scan, overload or break the security or integrity of the Service;
• access the Service by automated means other than the official API, or circumvent credit, rate, storage or account limits, including by creating multiple accounts;
• resell, sublicense or provide the Service to third parties as a service, unless agreed in writing;
• submit content that is illegal, including child sexual abuse material or content that incites violence or hatred.

10. API

API access is available on the plans that include it. API keys are personal to your account: keep them secret, and revoke a key immediately if you think it has been exposed. You are responsible for all usage made with your keys. API usage draws from your account's credits and is subject to the rate limits in the API documentation. If you build the API into your own product, you must give your users information equivalent to section 3 and must not present our results as proof. We may change the API with reasonable notice; we will give at least 30 days' notice of changes that are not backwards-compatible, except where needed for security or legal reasons.

11. Certificates of analysis

On paid plans you can create a signed certificate of a check. A certificate records, at the time it was issued, the results of the automated analysis, the number of words, the language, a cryptographic fingerprint (SHA-256) of the analysed text, and, if you choose, the document title and your name. We sign it with our private key and publish a verification page at probator.ai/verify/<certificate ID>.

• What a certificate proves. It proves that Probator.ai produced those results for a text with that fingerprint at that time. It does not prove who wrote the text, that the text is original, or that it was written without AI, and you must not present it as such.
• Public information. Anyone with the certificate ID can see the details listed above on the verification page. The text itself is not shown there, but it is included in the PDF if you choose so. Share certificates only with people you want to see them.
• Revocation. You can revoke a certificate at any time in your account; the verification page then shows it as revoked. We may revoke a certificate obtained in breach of these Terms, for example by manipulating the text or the Service. Certificates are deleted when you delete your account.
• No alteration. You must not alter a certificate or create documents that imitate one. Any change to the signed details invalidates the signature.
• Human review record. If you add a human review record, the certificate also shows the name you give as reviewer, your statement that you reviewed the text and take editorial responsibility for it, the time and results of your first check, and the share of words that changed between the two checks. We compute the times and the change from both versions; the statement is yours, and you are responsible for it being true. A review record does not by itself establish that a legal exception applies to you.
• Disclosure labels. We offer ready-made AI disclosure texts that link to a certificate. They are suggestions: you choose which one to use and you are responsible for it being accurate and for meeting any disclosure obligation that applies to you.

12. Our intellectual property

The Service, including our software, detection model, plagiarism index, design and brand, belongs to Spawncore or its licensors and is protected by law. These Terms give you a personal, non-exclusive, non-transferable right to use the Service while your account is active; they do not transfer any intellectual property to you. Feedback you send us may be used to improve the Service without obligation to you.

13. Availability and changes to the Service

We work to keep the Service available and secure, but we do not guarantee that it will be uninterrupted or error-free. We may carry out maintenance and may change, add or remove features. If a change materially reduces the paid features you rely on, we will tell you in advance and you may cancel and receive a proportional refund of any prepaid period.

14. Liability

If you are a consumer, nothing in these Terms limits your statutory rights, and we are liable in accordance with the law. We are not liable for losses that were not foreseeable, or for decisions you or others take on the basis of results despite section 3.

If you are a business customer, to the extent permitted by law: (a) the Service is provided "as is", and we exclude all implied warranties, including fitness for a particular purpose and accuracy of results; (b) we are not liable for indirect or consequential loss, loss of profit, revenue, data or goodwill; and (c) our total liability under these Terms in any 12-month period is limited to the amounts you paid us in that period.

Nothing in these Terms excludes or limits liability for death or personal injury caused by negligence, for fraud, for wilful misconduct or gross negligence, or any other liability that cannot be excluded or limited by law.

15. Suspension and termination

You can delete your account at any time in Account → Privacy & data. We may suspend or terminate your access if you seriously or repeatedly breach these Terms, if required by law, or to protect the Service or other users. Where reasonable, we will warn you first and give you the chance to export your data. If we terminate a paid subscription without a breach on your part, we refund any prepaid, unused period. On termination we delete your account data as described in our Privacy Policy.

16. Changes to these Terms

We may update these Terms, for example to reflect changes to the Service or the law. We will notify you of material changes by email or in the Service at least 30 days before they take effect, and ask you to accept them when you next sign in. If you do not agree, you may cancel and delete your account before the changes take effect; paid subscribers receive a proportional refund of any prepaid period.

17. Governing law, complaints and disputes

• These Terms are governed by Portuguese law. If you are a consumer, you also keep the protection of the mandatory laws of your country of residence, and you may bring proceedings in the courts of your country of residence.
• Business customers agree that the courts of Lisbon, Portugal, have exclusive jurisdiction.
• Please contact us first at hello@probator.ai; we try to resolve every complaint quickly.
• Complaints book. Consumers can file a complaint in the electronic complaints book (Livro de Reclamações Eletrónico) at www.livroreclamacoes.pt.
• Alternative dispute resolution. Consumers may refer a dispute to an alternative dispute resolution entity. In Portugal, these include the [competent consumer arbitration centre for the company's seat] and the CNIACC – Centro Nacional de Informação e Arbitragem de Conflitos de Consumo (www.cniacc.pt). More information is available on the Consumer Portal at www.consumidor.gov.pt.

18. General

These Terms, together with the AI Policy, Privacy Policy, Cookie Policy and, where applicable, the Data Processing Agreement, are the entire agreement between you and us about the Service. If any provision is found invalid, the rest remains in force. A failure to enforce a right is not a waiver. You may not transfer your rights under these Terms without our consent; we may transfer them to a company that takes over the Service, provided your rights are not reduced. These Terms are available in English and Portuguese; for consumers resident in Portugal, the Portuguese version prevails.

Annex: model withdrawal form