Privacy.

1. Controller

Further provider details are in the legal notice.

2. Website and API delivery

Every HTTP request necessarily transmits the requesting IP address and normally the date and time, method, path and query, response status and size, referrer, and user agent. Textus and its hosting provider, Hetzner Online GmbH in Germany, process these data to deliver the requested resource and to keep the service secure and reliable. The API access-log configuration omits query arguments and referrers; older log rotations and bounded server error diagnostics may still contain request details. A supplied or generated X-Request-ID may also appear in bounded error diagnostics. Do not place personal data or secrets in a URL, search term or request ID.

The legal basis is Article 6(1)(f) GDPR: the legitimate interests in secure, abuse-resistant, and technically reliable operation. Standard web-server access logs rotate daily; the server keeps the current file plus 14 daily rotations. Bounded application diagnostics are retained only while needed for troubleshooting, security, or legal claims and currently have no separate automatic deletion schedule. Data connected with a concrete incident or claim may be kept separately for as long as that purpose requires.

3. API protection

For rate limiting, the client IP address is transformed with a secret-keyed hash and used in short one-minute request windows. Textus does not retain the plain IP address in the rate-limit database. Expired counters are removed opportunistically during later API requests. The legal basis is Article 6(1)(f) GDPR, specifically protection against misuse and maintaining availability.

3a. Catalogue search and product-stage demand statistics

When enabled, Textus aggregates requests to its free catalogue to understand which texts, languages, types and bibliographic names are requested and where discovery fails. It also counts, per public resource ID and calendar day, payment challenges issued, first settled deliveries and receipt recoveries delivered. The statistics contain a calendar day in Europe/Berlin, bounded search and filter labels, request and result counts, purchase-availability counts, error categories, response timing, anonymous product-stage counts and a coarse, self-declared client family. A client family is not a verified agent identity. Additional catalogue pages and recognised Textus test traffic are counted separately from first-page search requests.

These statistics do not contain client IP addresses, cookies, persistent visitor identifiers, request IDs, raw user-agent strings, payment signatures, wallet addresses, receipt fingerprints or transaction references. Product-stage rows contain only the public resource ID and stage; they are not joined to payment receipts, search requests or individual profiles. They therefore do not establish a buyer-level conversion funnel. Obvious email addresses, URLs, network addresses and credential-like strings are suppressed before search labels are stored. This safeguard cannot reliably remove all personal information from free text: send short subject or title terms, not complete prompts, personal details or secrets.

The purpose is limited improvement of catalogue discovery and content planning; the legal basis is Article 6(1)(f) GDPR. The private statistics are restricted to the current calendar day and the preceding 13 days. Older rows are removed on subsequent collection and through operator maintenance; reporting never includes expired days. Maintenance must be kept running, including periods without traffic. Exported operator reports require separate access and deletion controls; expiry in the database does not erase an exported copy. Textus does not publish raw queries or send the statistics to an advertising or third-party web-analytics service.

3b. Optional MCP catalogue discovery

The optional Textus MCP endpoint at https://api.textus.dev/mcp provides the same public catalogue discovery function to compatible AI clients. A request can contain a short search term and the optional public filters language, resourceType, author, collector, purchaseAvailable, page, limit and catalogue snapshot. Do not send complete prompts, personal details, credentials, payment signatures, wallet material or other secrets in these fields. The endpoint does not receive an AI-client chat history, create an account, use a wallet, start a payment or return paid full text.

Textus does not store the submitted MCP filter values in application logs. The web-server access logging described in section 2 and the existing, redacted catalogue-demand statistics described in section 3a can still apply to the corresponding HTTP request. Recipients, retention periods, safeguards and legal bases remain those described in sections 2, 3 and 3a.

4. x402 payments and delivery receipts

An unsigned request receives a payment challenge and does not initiate settlement. If a client submits a PAYMENT-SIGNATURE, Textus processes the signed authorization, public payer and recipient addresses, resource and payment requirements, amount, asset, network, validity period, nonce, and technical request data. This is necessary to verify the authorization, settle the purchase, deliver the exact artifact, prevent duplicate settlement, and support recovery.

Textus stores a receipt fingerprint, the purchased resource and artifact identity, delivery digest and path, accepted requirements, settlement status, public transaction reference, network, public payer address, retry or reconciliation state, and timestamps. The raw PAYMENT-SIGNATURE is not stored in the receipt database.

The legal bases are Article 6(1)(b) GDPR for processing needed to perform or prepare the purchase contract, Article 6(1)(f) GDPR for settlement integrity, fraud prevention, and defence of claims, and Article 6(1)(c) GDPR where statutory record-keeping applies. Receipt evidence is retained while needed for immutable delivery recovery, the perpetual licence, accounting obligations, or legal claims. It is not subject to routine deletion while one of those purposes continues.

5. Coinbase CDP and the Base blockchain

Textus sends the signed payment payload and matching requirements over HTTPS to the hosted Coinbase Developer Platform x402 facilitator for verification and settlement. Coinbase is used as a processor under the CDP terms; the applicable Coinbase contracting entity depends on the operator’s CDP account. Processing may take place outside the European Economic Area, including under the standard contractual clauses described in the CDP terms and Coinbase privacy notice.

Successful settlement occurs in USDC on Base Mainnet. Blockchain records—including public wallet addresses, token amount, transaction hash, and time—are public, independently replicated, and effectively permanent. Textus cannot erase or alter data recorded on the Base blockchain.

6. Support email

If support is contacted, Textus processes the sender and recipient addresses, message headers and content, attachments, and the non-secret evidence voluntarily supplied. Email infrastructure is hosted by Uberspace in Germany. The legal bases are Article 6(1)(b) GDPR where the message concerns a contract and Article 6(1)(f) GDPR for answering other legitimate enquiries and defending claims.

Support correspondence is retained only for as long as needed to resolve the request and meet contractual, accounting, security, or legal requirements. Never send a payment signature, seed phrase, private key, wallet recovery material, or other credentials.

7. Recipients, links, and required data

Data are disclosed only where needed to the hosting and email providers, the Coinbase facilitator, the public Base network, advisers or authorities where legally required, and service operators who need access for secure operation. External websites are contacted only when their links are opened.

There is no statutory requirement to browse Textus. Technical request data are necessary to deliver the site and API; signed payment data are necessary to settle and recover a purchase. Without them, the corresponding service cannot be provided.

Textus does not create advertising profiles. Automated technical checks compare the request, rate limit, signature, payment requirements, and settlement result. Coinbase also performs automated transaction and address screening, including sanctions and risk checks. These checks can reject a request or permit settlement and delivery. Support can review delivery and reconciliation issues through the contact channel above; it cannot override blockchain settlement or applicable legal restrictions.

8. Your rights

Subject to the statutory conditions, data subjects may request access, rectification, erasure, restriction, and portability of their personal data, and may object to processing based on legitimate interests. Consent may be withdrawn for the future, although Textus currently does not rely on consent for the processing described here. Statutory retention duties, contractual recovery evidence, legal claims, and the technical permanence of public blockchain records can limit erasure.

Requests can be sent to me@marcusscheller.com. Data subjects may also complain to a supervisory authority. The authority responsible for the controller is the Brandenburg Commissioner for Data Protection and the Right of Access to Files, Stahnsdorfer Damm 77, 14532 Kleinmachnow, Germany, lda.brandenburg.de.