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API Conditions

Last updated: 2026-10-13

1. SCOPE AND ACCEPTANCE

1.1 These API Conditions apply to any Customer who uses the application programming interface (the "API") of the service operated by Wizorg LTD (the "Provider"). They supplement the Terms and Conditions of Sale, in particular Articles 8.7 and 15, which remain applicable. In case of conflict on the use of the API, these API Conditions prevail.

1.2 These API Conditions are accepted separately, by ticking the dedicated box, before the first API key is created in the customer area. Where the Customer uses the API for professional purposes, Wizorg LTD may ask for identification information (company name, SIREN/SIRET number, professional address, billing email) to check their professional status.

1.3 Access to the API is included in the LettreX+ subscription, with no additional fee, and is available to Customers with an active subscription. Every mailing sent through the API is charged at the rates applicable to the subscription when the request is submitted (see Article 9).

2. FEATURES COVERED

The API allows the Customer to create a mailing from its own application, choose the sending mode and transmit the documents and addresses. When a request is accepted, the response contains the reference of the mailing, its status, the amount charged and the currency. Error handling returns an explicit message when a request is rejected. The features available are those described in the API documentation and may evolve (see Article 11). The cancellation of a mailing through the API is possible only as long as the mailing has not been handed over to the postal fulfilment provider.

3. SENDING MODES

The sending modes available through the API are the green letter, the tracked letter and the registered letter with acknowledgment of receipt, for the destinations shown in the customer area. The green letter includes no tracking and no proof of delivery. The tracked letter includes a tracking number and the tracking events made available by the postal operator. The registered letter includes the proof of deposit, the tracking and the acknowledgment of receipt supplied by the postal operator. The delivery times shown are indicative and are not guaranteed.

4. PROOF OF SENDING AND TRACKING

For each mailing, the Customer has access in the customer area to the status of the mailing and, for tracked and registered letters, to the tracking number and the proofs supplied by the postal operator (proof of deposit, acknowledgment of receipt) as soon as the postal operator makes them available, in the format in which they are provided. The API itself does not currently provide a separate way to retrieve the tracking number or the proofs. These elements and the history of mailings remain accessible during the subscription and for one (1) year after its end. Wizorg LTD does not guarantee the evidential value of the proofs beyond that recognised by law for the documents supplied by the postal operator.

5. RESPECTIVE RESPONSIBILITIES

The Customer is responsible for content, addresses, instructions, lawfulness and duplicate requests. Wizorg LTD is responsible for proper receipt, processing and performance of accepted requests, including through its providers. Consumer rights and only the lawful exemption grounds in Article 11 of the Terms remain applicable. The professional liability cap in Article 15 does not apply to consumers using the API.

6. AVAILABILITY AND SUPPORT

Wizorg LTD makes reasonable efforts to keep the API available 24 hours a day, 7 days a week, without guaranteeing uninterrupted availability. Maintenance operations may cause temporary interruptions; when possible, they are carried out outside business hours. Technical support is provided by email at contact@lettrex.co, Monday to Friday, 9:00 AM - 6:00 PM (CET), with an answer within forty-eight (48) business hours. Incidents affecting the API are handled as a priority once identified. Wizorg LTD is not liable for unavailability caused by maintenance, third-party providers or force majeure.

7. SECURITY OF API KEYS

The Customer keeps its API keys confidential, stores them only on its servers, never in publicly accessible code, and does not share them. In case of loss or suspected compromise, the Customer revokes the key immediately from the customer area and informs Wizorg LTD. Wizorg LTD may revoke or suspend a key to protect the Service, in case of abuse or excessive use, or in case of non-payment. The Customer is responsible for requests made with its keys until revocation. Each key can be identified by its name and its last use in the customer area.

8. PERSONAL DATA AND CONFIDENTIALITY

8.1 Where the Customer, outside a purely personal or household activity, sends through the API the personal data of its own correspondents (senders and recipients), the Customer is the data controller and Wizorg LTD acts as processor within the meaning of Article 28 of the GDPR, for the sole purpose of executing the mailings. Wizorg LTD processes this data only on the documented instructions of the Customer, ensures that the persons authorised to process it are bound by confidentiality, applies appropriate security measures, assists the Customer with data subjects' requests, deletes or returns the data at the end of the contract and may use sub-processors (postal fulfilment provider, hosting provider) bound by equivalent obligations. The list of providers and transfers is given in the Privacy Policy. A data processing agreement can be requested at contact@lettrex.co.

8.2 Wizorg LTD keeps confidential the content of the documents, the files, the addresses and the metadata transmitted through the API, and gives access to them only to authorised staff and providers where strictly necessary to perform the mailing or to resolve an incident.

9. PRICES AND INVOICING

API mailings are billed separately at the rates displayed when requested, including options and VAT. The subscription is billed in thirty (30) day periods under the Terms. Invoices are available in the customer area and may be disputed at contact@lettrex.co. Payment uses the method registered in the customer area.

10. ERRORS AND CANCELLATIONS

The Customer is responsible for address errors, duplicates and incorrect files from their application. Technical cancellation through the API, where offered, is possible only before handover to the postal provider. This technical limit does not exclude consumer statutory rights, legally due refunds or Protection option guarantees.

11. CHANGES TO THE API

Wizorg LTD may change the API or its documentation to maintain security, performance or compatibility, and will inform the Customers concerned by email within a reasonable time before any change that would break an existing integration, except in case of urgency for security reasons.

12. END OF THE CONTRACT

When the subscription ends, the API keys are deactivated. The Customer can export its mailing history, proofs and invoices from the customer area during the subscription and for one (1) year afterwards. After this period, the data is deleted or anonymised, except for the data that must be kept by law, as described in the Privacy Policy.

13. GOVERNING LAW

The API Conditions are governed by French law. For a professional Customer, jurisdiction is as stated in Article 15 of the Terms. Consumers retain access to the courts competent under mandatory rules and to consumer mediation. API use does not change consumer status.