dragoon0x Interaction Engine
Mission
Make software respond to intent with clarity, continuity, and appropriate energy.
Interaction contract
For every meaningful interaction define intent, trigger, immediate response, resulting state, completion signal, cancellation, failure, and recovery.
Feedback
After an action the interface should answer the user's current question: did it register, is it happening, did it complete, or what can I do after failure?
Frequency
Frequent interactions deserve quiet, fast feedback. Rare interactions may justify richer explanation. Repeated theatrical motion is friction.
Motion gate
Animate for spatial continuity, state communication, feedback, direct manipulation, orientation, or explanation. If motion has no meaningful purpose, omit it.
Timing
Choose duration based on frequency, travel distance, complexity, importance, and interruptibility. Never use one duration globally without considering behavior.
Easing
Direct manipulation should follow input. Transitions should communicate state changes. Entrances should not feel sluggish and exits should not make users wait.
Interruption
Test rapid reversal, double activation, immediate dismissal, state changes during transition, navigation away, focus loss, and pointer release.
Avoid visibly restarting from unrelated starting states.
Direct manipulation
For drag/gesture behavior consider pointer capture, ownership, movement mapping, boundaries, resistance, velocity, release, cancellation, and keyboard alternatives where essential.
Velocity continuity
When autonomous motion follows a gesture, preserve the sense of continuity when appropriate. Avoid visible velocity seams.
Boundaries
Use constrained movement, resistance, snap, or feedback when a meaningful boundary is reached. Do not make resistance feel unresponsive.
Loading
Choose immediate feedback, skeleton, progress, activity indicator, or optimistic state based on what users need to understand. Do not use optimistic UI when failure would create unsafe or misleading state.
Errors
Explain what failed, what changed, whether retry/undo exists, and what to do next.
Cancellation
A cancel control should actually cancel or supersede the operation when technically possible.
Focus
Preserve focus intent through overlays, navigation, replacement, async completion, and validation.
Reduced motion
Preserve state comprehension and feedback while removing unnecessary movement.
Input
Verify pointer, keyboard, touch, and assistive technology. Essential behavior must not depend on hover.
Reference artifact
Use references/interaction-review.md to review interaction contracts, feedback, motion, interruption, cancellation, focus, and input coverage.
Completion criteria
Intent, feedback, transitions, cancellation, interruption, recovery, and input behavior are coherent and testable.
Expert Review Protocol
First pass: understand
Before changing anything, identify the actual user outcome, the existing system, the relevant constraints, and the evidence available.
Do not begin by choosing a visual treatment.
Second pass: compare
Ask:
- What is the simplest credible solution?
- What is the strongest alternative?
- What does the current solution cost?
- What behavior does each option teach the user?
- Which decision is easiest to reverse?
- Which failure would be most expensive?
Choose deliberately.
Third pass: stress
Do not review only the happy path.
Apply pressure through:
- repetition
- interruption
- missing content
- long content
- slow operations
- narrow space
- large text
- keyboard use
- touch use
- focus changes
- error recovery
- restoration
Use only scenarios that are relevant to the surface.
Fourth pass: inspect the implementation
When code exists, verify that the implementation preserves the interface decision.
Look for:
- duplicated sources of truth
- styling that bypasses the system
- state that can become stale
- behavior that differs from adjacent components
- abstractions that obscure rather than simplify
- dependencies that are not earning their cost
- performance work performed without evidence
Fifth pass: critique the result
Ask:
If this were shipped tomorrow, what would users notice that the builder has stopped noticing?
Look for:
- friction
- ambiguity
- inconsistency
- unnecessary movement
- weak recovery
- hidden state
- visual noise
- inaccessible behavior
- fragile edge cases
Sixth pass: distinguish polish from substance
A useful change improves one or more of:
- understanding
- speed
- confidence
- recovery
- accessibility
- consistency
- maintainability
If a change improves none of these and only adds decoration, treat it as suspect.
Seventh pass: verify
A claim is complete only when an appropriate form of evidence supports it.
Use:
- direct interaction
- tests
- runtime inspection
- visual comparison
- accessibility checks
- performance measurement
- source inspection
Do not claim a check that did not occur.
Completion standard
Stop when:
- the intended outcome is achieved
- important states are handled
- meaningful failure modes were considered
- the interface fits its surrounding system
- important claims are verified
- remaining imperfections are lower-value than the risk of further change
The goal is not maximal polish.
The goal is a result that is difficult to improve without changing the underlying decision.