Master’s thesis · Interaction design
Two interactive prototypes exploring how tone, modality and explanatory cues shape trust, safety and a sense of control in everyday chatbot conversations.
The brief
People increasingly turn to generative AI for everyday reflection and support, not just quick answers, yet most chatbots are still plain text boxes with no sense of role or boundaries. For our master’s thesis in Human Computer Interaction, we explored how tone, interaction design, and modality shape trust, safety, and a sense of control when talking to a GenAI assistant.
We designed and tested two Framer prototypes, then studied how everyday users experienced them through interviews and think aloud testing.
Research
We ran exploratory interviews first, then scenario based prototype testing with a think aloud protocol, asking participants to complete tasks and reflect on the assistant’s responses as they went.
8
participants interviewed, everyday users
7
went on to think aloud prototype testing
2
rounds of interactive Framer prototypes
Synthesis
Research insight
Users wanted clearer expectations about how the assistant would respond.
Design decision
We created three clearly defined conversational roles with distinct purposes and boundaries.
Research insight
Participants preferred structured conversations over completely open ended interaction.
Design decision
Prototype 2 introduced guided interactions and more predictable conversation paths.
Research insight
Transparency increased confidence in the assistant.
Design decision
We incorporated source references, disclaimers and clearer communication about AI limitations.
Concept, prototype one
Instead of one generic assistant, users chose between three conversational roles, giving the system a clearer, more legible identity before the conversation even started.
Generative AI is often experienced as text appearing on a screen. We wanted the assistant to feel present without pretending to be a person, so we gave it a visual companion rather than a chat window alone.
We explored the balance between approachability and clear AI boundaries. Early on, the concept was inspired by the metaphor of a spirit in a lamp, exploring how an AI could appear when needed while remaining clearly identifiable as an AI rather than a person. This evolved into an abstract visual companion that felt expressive and socially present without implying genuine emotion or consciousness.
Each mode had its own visual identity, giving conversations a distinct tone from the start: Personal Reflection used a broader range of expressions to support reflective conversation; Analytical Assistant had its own look, including glasses and a clipboard, and expressions that reinforced structured, analytical reasoning; Source Critical Guidance had its own identity and expressions reinforcing evaluation, questioning and critical assessment.
Personal Reflection
Broader range of expressions, supporting open, reflective conversation.
Analytical Assistant
Own identity and expressions reinforcing structured, analytical reasoning.
Source Critical Guidance
Own identity and expressions reinforcing evaluation and critical assessment.
A few examples of Personal Reflection’s expressions.
While each mode’s visual language stayed consistent throughout a conversation, the companion also shifted expression when input was received, while a response was generated, and when it appeared, making system activity visible without relying on additional interface elements.
Listening
Processing
Responding
Together, these two decisions gave the companion a way to communicate both conversational tone and system activity at the right moments. Its abstract form kept it clearly identifiable as AI rather than a simulated person.
Low fidelity wireframes in Figma helped us structure the interface and the user flow before investing in visual design. For prototype one, they concretised the three mode concept: a start page where users pick a mode, and the conversation structure within each one. These wireframes became the foundation for the next, more refined iteration.
Before building the interactive prototypes, we mapped every conversational path to understand user decisions, system behaviour and interaction states.
User flow diagrams mapping each mode's conversation path.
Prototype 1: Three user flows exploring how Analytical, Personal and Source-Critical conversations guide users through different interaction styles.
Visual & interaction design
Core purple
Soft lavender
Background
Ink text
A minimal layout, a single purple palette used consistently across background, buttons and the AI figure, and simple, readable typography, all to reduce memory load and keep users oriented in a conversation rather than a control panel.
Mode cards (icon, title, short description) made the assistant’s options visible before the conversation began. Chat bubbles, a “Thinking…” progress indicator, and a pulsing microphone animation for voice input gave the system a visible, predictable state at every step.
Transparency & boundaries
Explicit disclaimers and source references worked as boundary markers throughout, small signals that told people when to trust the assistant and when to look elsewhere:
“For medical advice, consult reliable sources or your GP”, in the source critical mode.
An information icon with “This is general guidance, not professional medical advice” in the text based mode.
The voice mode telling users the conversation wasn’t recorded, and stating its purpose plainly.
Testing & iteration
Testing showed that interaction style mattered more than simply offering multiple AI personalities. Rather than refining all three roles further, we focused the second prototype on comparing text and voice interaction.
Testing prototype one told us tone and structure mattered more than the number of roles on offer, so prototype two narrowed the focus to compare modality directly:
Open chat became button based choices. Predefined options made it clearer what the system could offer at each step.
Voice got its own visual language. A record button, pulsing mic and audio waveform made spoken input visible and easy to follow.
Three roles became two topics. “Sleep & energy” and “Summer holiday tips” kept the comparison focused on modality, not role.
“Structured, bounded answers felt more trustworthy than open ended ones.”
key pattern across think aloud sessions
Voice based mode
Text based mode
User flow diagrams for the refined text and voice based chat.
Prototype 2: Updated user flows comparing structured text interaction with voice interaction after insights from user testing.
The result
Prototype 1 walkthrough
Prototype 2 walkthrough
Bounded, structured responses built more critical trust than open ended ones.
Empathetic tone created a stronger sense of emotional safety in the personal mode.
Source references often worked as credibility markers rather than links people actually checked.
Voice interaction had mixed reception, some found it robotic or exposing, others found it more natural.
Reflection
Small cues carry a lot of weight. A disclaimer, a progress indicator, a tone of voice, these shaped trust far more than any single feature.
Structure supports agency. People felt more in control with clear, bounded choices than with an open field and no guardrails.
Research and design fed each other. Working across interviews, prototyping and testing together taught me to let real user language reshape the design, not just validate it.
I’d love to talk about research, trust, and designing for AI driven products.