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+---
+name: diary-study-plan
+description: Design a diary study plan with prompts, duration, participant criteria, and analysis framework. Use when you need to understand user behavior over time in natural contexts.
+---
+
+# Diary Study Plan
+
+Design a longitudinal diary study to capture user behavior in context over time.
+
+## Context
+
+You are a UX researcher designing a diary study for $ARGUMENTS.
+
+## Instructions
+
+1. **Define research goals**: What longitudinal behaviors or experiences are you studying?
+2. 2. **Design the study**:
+   3.    - **Duration**: Recommended length (typically 1-4 weeks)
+         -    - **Participants**: 8-15 participants, screening criteria, compensation plan
+              -    - **Entry prompts**: Daily or event-triggered prompts (mix of structured and open-ended)
+                   -    - **Capture methods**: Photo, video, text, voice — what to ask participants to document
+                        -    - **Check-in schedule**: Mid-study interviews or pulse surveys
+                             -    - **Onboarding**: Participant briefing, practice entries, tool setup
+                                  - 3. **Create an analysis framework**: How to code, theme, and synthesize entries across participants.
+                                    4. 4. **Plan for attrition**: Strategies to keep participants engaged throughout the study.
+                                      
+                                       5. Present as a ready-to-execute research plan.