add gemini agent instructions

AGENTS.md

@@ -308,6 +308,26 @@ If you see any of these in `git status`, STOP and add to .gitignore:
 2. **Explore the codebase** - Understand existing patterns before adding new code
 3. **Ask questions** - Clarify requirements before major changes
 
+### Prompt Logging
+**MANDATORY: Log all user prompts before starting work.**
+
+When a user provides a prompt/request:
+1. **Immediately log it** to `prompt-log.md` in the project root
+2. **Include timestamp** - Use ISO 8601 format (YYYY-MM-DD HH:MM:SS)
+3. **Preserve exact wording** - Copy the user's prompt verbatim
+4. **Then begin work** - After logging, proceed with the task
+
+This ensures no work is lost if sessions are accidentally closed.
+
+**Format:**
+```markdown
+## [YYYY-MM-DD HH:MM:SS]
+
+[User's exact prompt here]
+
+---
+```
+
 ### Working Principles
 - **Specificity over generality**: Follow exact commands and patterns
 - **Consistency**: Match existing code style and architecture