Core Concepts

This page defines the core terms and relationships used in MOMENTUM. It describes what things are, not how to run the day-to-day workflow. Practical usage lives in the Workflows pages.

MOMENTUM is built around one central idea:

Product strategy is a written, versioned Single Source of Truth.

The MOMENTUM Core Flow

flowchart LR
    U[Human Input<br/>Observations · Feedback · Ideas] -->|Structured by prompts| E[Evidence]
    U -->|Intentional decisions| S[Strategy<br/>SSOT]

    E -->|Informs| S

    S -->|Cascade| A[Artifacts<br/>Epics · Stories · Docs]

    A -->|Production signals| E

    style U fill:#e3f2fd
    style S fill:#e8f5e9
    style E fill:#fffde7
    style A fill:#f3e5f5

Human input is the starting point for the MOMENTUM process, providing observations, feedback, and ideas. Strategy serves as the single source of truth, guiding the creation of downstream, regenerable artifacts. Evidence continuously feeds learning back into the strategy without bypassing intentional decisions.

Strategy

Definition:
Strategy is the authoritative description of what the product is, what it does, for whom, and why. It is both the condensed behavioral specification (the "what") and the strategic intent (the "why"). It is written at a level of clarity that allows rebuilding the product with the same scope and behavior.

Characteristics:

• Explicit and written down
• Independent from implementation
• Versioned and reviewed
• Long-lived until deliberately changed
• Concise but complete
• Describes intent, scope, constraints, and success criteria

Where it lives:

• product-strategy.md

The momentum framework comes with multiple prompts that help PMs to refinine the strategy. The Agents can help to identify gaps, suggest improvements or highlight inconsistencies.

Evidence

Definition:
Evidence is the detailed rationale and proof that underpins the strategy. If strategy is the condensed "what" and "why," evidence provides the exhaustive justification, including the full context, data, research, and trade-offs.

Evidence does not decide. It informs decisions.

Characteristics:

• Descriptive, not prescriptive
• Grounded in reality
• Can support or challenge strategy
• Grows over time
• Separate from strategy but directly linked

Where it lives:

• product-evidence.md
• Supporting files under /discovery/* when the evidence grows

Decisions

Definition:
Decisions are intentional commitments made by the Product Manager based on evidence, constraints, and judgment. A decision changes strategy.

Key properties:

• Explicit and deliberate
• Traceable to evidence or rationale
• Reversible when new evidence appears

If a choice cannot be traced back to a decision, it is accidental. If a decision is not reflected in strategy, it does not exist.

Artifacts

Definition:
Artifacts are downstream representations of strategy in executable or communicable form. They express strategy. They do not define it.

Characteristics:

• Derived from strategy
• Replaceable and regenerable
• Scoped to a specific purpose
• Allowed to change frequently

Where they live:

• /delivery/epic-*/epic-*.md
• /delivery/epic-*/story-*.md
• Other purpose-specific folders as needed

If strategy is clear, artifacts can be recreated.

A Simple Example

Strategy:

“We help individual users understand their own activity history. Collaboration and shared views are explicitly out of scope.”

Evidence:

• Interviews show users regularly review their own history to understand what changed over time
• Support feedback indicates users want clearer timelines and filters for their own activity
• Early production signals show repeated individual usage patterns, but no collaboration demand

Decision:

“Do not support sharing or collaboration in the first iteration. Focus on personal history, clarity, and filtering.”

Artifacts:

• Epic: Activity History
• Story: View my own activity over time
• Story: Filter activity by type and date range
• Non-goal captured in strategy: No shared dashboards

The artifacts express the strategy. They do not reinterpret it.

Human Ownership and AI

MOMENTUM does not automate product management.

The Product Manager owns Strategy, Decisions, Trade-offs and Accountability.

AI is used to structure human input, maintain consistency across files, propagate changes from strategy into artifacts and reduce manual coordination work.

AI assists. Humans decide.

Why Git Matters (Conceptually)

Strategy benefits from version control for the same reasons code does:

• Decisions are traceable
• Changes are reviewed and approved (optionally)
• History is preserved
• Intent is explicit

Git is not used to make strategy technical. Git is used to make strategy durable.

Summary