A basis for understanding.

In a matter of seconds, a language model can produce text that is detailed, coherent and persuasive. That text can look like solid evidence. Fluency alone does not make it evidence.

What looks like analysis may be an assumption. What reads like a conclusion may be a guess. What is presented as fact may be a reconstruction from memory. When these blend into a fluent passage, a human reader—even a careful one, at times—can lose the ability to distinguish assumptions, guesses and facts.

The more costly and irreversible the decision, the greater the cost of this mistake.

Some projects begin with boundaries that are not yet understood. Even knowledgeable participants may discover important questions they did not know to ask.

RDEP governs how research and engineering work moves from an uncertain idea to a justified decision and authorized action. It connects problem definition, investigation and testing with feasibility, requirements, architecture and human decisions. Its focus is the adequacy of the knowledge, evidence and reasoning behind that progression. That assessment also asks whether the work can be carried out with the available time and resources, which outcomes are actually required, and what could go wrong. A technically attractive idea still needs a realistic basis before people commit to it.

RDEP is designed to reduce uncertainty before commitment. That sounds simple. It is not, because the pressure is always in the opposite direction: start now; we will figure it out later.

To do this, RDEP requires the different bases of understanding and decision-making to remain distinct and not be used interchangeably as work proceeds. Evidence remains separate from assumptions. An observation remains separate from its interpretation. A proposal remains separate from a decision. And what we do not know is recorded as unknown, rather than filled in with a plausible sentence.

RDEP requires the basis of important conclusions and decisions to be recorded, so that “Where did this come from?” can be answered from the available sources. If that basis is missing, the gap must remain explicit.

As a project expands, more specialties become involved and terminology and abbreviations accumulate, the accountable human may no longer be able to clearly assess the basis of proposals or the consequences of decisions.

RDEP addresses this through a set of connected mechanisms: clarifying the problem and scope, breaking down complex questions, distinguishing evidence from assumptions, preserving the origin of information, examining alternatives and their consequences, recording unknowns, and allowing questions and reconsideration before commitment.

Clear language and explained terminology support this process. The aim is for the human to understand what decision they are making, on what basis, within what limitations and with acceptance of which risks.

Language quality matters alongside these mechanisms. In developing RDEP, selected parts of ASD-STE100 have been examined, including approaches to clear statements, consistent terminology and identifying who is responsible for each action. Some bounded rules arising from this examination have been incorporated into the Engineering Method and the documents it governs.

Because ASD-STE100 was developed for English, extending this approach to multilingual communication requires adapting expression to each language. This direction has been pursued within RDEP, and drafts have been prepared. It does not amount to full adoption of the standard or implementation of a comprehensive language control across all conversations.

The aim is to support informed human understanding: clear language must work alongside traceable evidence, an explanation of the reasoning, explicit unknowns and examination of the consequences of decisions.

It is not document production. Complete documentation, a clean repository and passing automated tests do not establish scientific or engineering maturity. Producing an artifact never, by itself, means passing the stage for which that artifact was created.

It is not a tool. Tools, scripts and agents can enforce policy, but they do not define it. The moment a tool becomes a second source of truth, the very problem RDEP was created to address has returned.

It is not a replacement for the human. Reserved decisions and risk acceptance remain with the accountable human; assigning work to an agent does not transfer that authority.

RDEP provides a framework for collaboration between humans and AI agents in research and engineering: the necessary questions, required evidence, assumptions and unknowns must be clear, and each participant's decision-making responsibilities and authority boundaries must be specified.

Facts, observations, measurements, inferences, assumptions, hypotheses, proposals and decisions are not interchangeable. Repeating a statement, presenting it confidently, recording it in a document or obtaining agreement from several agents does not prove it.

The aim is to reduce uncertainties that could change the project's direction before making decisions that are difficult to reverse. Progress means gaining a better understanding and being able to examine its basis. More text, diagrams or code do not, on their own, demonstrate such progress.

RDEP's rules do not depend on a particular model, vendor or application's proprietary memory. When a tool or agent changes, the basis of evidence and decisions must remain accessible, understandable and open to examination by the accountable human, enabling them to direct the project with informed judgment. RDEP's Core covers research and engineering definition through authorized entry into implementation; subsequent execution can be organized through appropriate controls that remain subordinate to the same principles.