EU AI Act Technical Documentation Checklist: Annex IV Requirements (2026) | MmowW

The Purpose of Technical Documentation Under the EU AI Act

Article 11 of Regulation (EU) 2024/1689 requires that technical documentation of a high-risk AI system be drawn up before that system is placed on the market or put into service and kept up to date. This documentation serves multiple purposes. It enables national competent authorities and notified bodies to assess compliance with the requirements of the Act. It provides a comprehensive record of how the AI system was designed, developed, and tested. And it creates accountability by documenting the decisions made throughout the system lifecycle.

Annex IV specifies what this technical documentation must contain. The requirements are detailed and comprehensive, reflecting the seriousness with which the EU legislature treats high-risk AI systems. This checklist walks through each section of Annex IV to help organisations prepare documentation that meets these requirements.

Section 1: General Description of the AI System

The first section of Annex IV requires a general description of the high-risk AI system. This encompasses the intended purpose of the system, the name and version of the system, how the AI system interacts with or can be used to interact with hardware or software that is not part of the AI system itself, the versions of relevant software or firmware and any requirement related to version update, and the description of all forms in which the AI system is placed on the market or put into service.

This section must also include a description of the hardware on which the AI system is intended to run, a description of the forms of data input and data output where applicable, and basic information about the product or system into which the AI system is integrated, where applicable. The general description should be sufficiently detailed that a technically competent reader can understand what the system does and how it operates at a high level.

Section 2: Detailed Description of System Elements

Annex IV Section 2 requires a detailed description of the elements of the AI system and of the process for its development. This is the most technically demanding section of the documentation requirement. It includes the methods and steps performed for the development of the AI system, including where relevant recourse to pre-trained systems or tools provided by third parties and how those have been used, integrated, or modified by the provider.

Section 2 also requires documentation of the design specifications of the system, specifically the general logic of the AI system and the algorithms. This includes the key design choices, the main classification choices, what the system is designed to optimise for and the relevance of the different parameters, and the decisions about any possible trade-offs made regarding the technical solutions adopted to comply with the requirements set out in the Act.

The description of the system architecture must explain how software components build on or feed into each other and integrate into the overall processing. This includes the computational resources used to develop, train, test, and validate the AI system. Documentation of data requirements must cover datasheets describing the training methodologies and techniques and the training datasets used, including their origin, scope, main characteristics, how the data was obtained and selected, labelling procedures, and data cleaning methodologies.

Section 3: Monitoring, Functioning, and Control

Section 3 of Annex IV addresses detailed information about the monitoring, functioning, and control of the AI system. This section documents the capabilities and limitations of the system in terms of accuracy, robustness, and cybersecurity. It must describe the levels of accuracy of the system and the relevant accuracy metrics, the known or foreseeable circumstances that may affect the level of accuracy, and the expected level of accuracy in view of the intended purpose.

The documentation must also address resilience against errors, faults, or inconsistencies that may occur within the system or the environment in which the system operates. This includes resilience against attempts by unauthorised third parties to alter the use or performance of the system by exploiting vulnerabilities, covering cybersecurity measures. The metrics used to assess these capabilities must be documented alongside the testing methodologies used to establish them.

Section 4: Risk Management System Information

Section 4 requires a description of the risk management system in accordance with Article 9. This creates a direct link between the technical documentation and the risk management process. The documentation must describe how the risk management system was established and implemented, what risks were identified and how they were evaluated, what risk treatment measures were adopted, and how residual risks were assessed and communicated.

This section should include evidence that the risk management system operates as a continuous iterative process, as required by Article 9. Documentation of risk assessments conducted at different stages of development, records of how risk management measures were tested and validated, and evidence of post-market monitoring integration all support compliance with this requirement.

Section 5: Changes During Lifecycle

Section 5 of Annex IV requires a description of any change made to the system through its lifecycle. This is particularly important given the iterative nature of AI development, where systems may be updated, retrained, or modified after initial deployment. Each significant change must be documented, including the nature of the change, the reason for the change, and the assessment of whether the change triggers a new conformity assessment.

The lifecycle documentation requirement reinforces the continuous nature of compliance under the EU AI Act. Technical documentation is not a static document produced once and filed away. It must be maintained and updated throughout the system's operational life. This means organisations need documentation processes that can accommodate ongoing changes while maintaining a clear audit trail.

Section 6: Standards Applied

Section 6 requires a list of harmonised standards applied in full or in part, the references of which have been published in the Official Journal of the European Union. Where no harmonised standards have been applied, Section 6 requires a detailed description of the solutions adopted to meet the requirements set out in Section 2 of the Act, including a list of other relevant standards and technical specifications applied.

This section documents the technical basis for the provider's compliance claim. Where harmonised standards exist and have been applied, they provide a presumption of conformity with the corresponding requirements of the Act. Where standards have not been applied, the provider must demonstrate through other means that the requirements have been met. In either case, the documentation must be specific about which standards or solutions were applied and how they address the applicable requirements.

Section 7: EU Declaration of Conformity

Section 7 requires a copy of the EU declaration of conformity referred to in Article 47. The declaration of conformity is a formal statement by the provider that the high-risk AI system complies with the requirements of the Act. It must contain the information specified in Annex V, including the name and address of the provider, the identification of the AI system, a statement that the declaration is issued under the sole responsibility of the provider, and a reference to the relevant harmonised standards or other technical specifications applied.

The declaration of conformity is more than a formality. It represents a binding commitment by the provider regarding the compliance of their AI system. The declaration must be kept up to date and made available to national competent authorities upon request.

Section 8: Post-Market Monitoring

The final section of Annex IV addresses the post-market monitoring system established by the provider in accordance with Article 72. This documentation must describe the mechanisms for collecting and analysing data about the system's performance after deployment, the processes for identifying and responding to incidents, and the procedures for updating the AI system based on post-market findings.

Post-market monitoring documentation connects the technical documentation to the ongoing operational phase of the AI system. It ensures that the documentation framework extends beyond initial development and deployment into the full lifecycle of the system.

Practical Documentation Management

Preparing and maintaining Annex IV-compliant documentation requires systematic processes. Each section involves different stakeholders, from development engineers to risk managers to legal teams. Organisations should designate clear ownership for each documentation section and establish review cycles that ensure documentation remains current.

The documentation must be available for inspection by competent authorities for a period of 10 years after the AI system has been placed on the market or put into service, as specified in Article 18. This retention requirement means organisations must maintain documentation management systems capable of preserving records over extended periods.

Building documentation practices into daily operations is more effective than attempting to compile documentation retrospectively. The WnowW Trust OS at mmoww.net/ai/app/ provides a framework for maintaining the kind of ongoing documentation discipline that Annex IV demands, helping organisations treat technical documentation as a living practice rather than a one-time project. Content verified against current regulations by Sawai Gyoseishoshi Office.

This article is for informational purposes only and does not constitute legal advice. Regulatory requirements change frequently — verify current rules with official sources. Built by Sawai Gyoseishoshi Office, Hiroshima, Japan.