Claude Code session wind down

dev_log_template.md

Dev Log Entry Template

This template codifies the section patterns that have emerged across 40+ dev log entries. Use it as a guide for consistency, but adapt freely when the session calls for different structure.

Flexibility: If a particular session needs different sections or organization, use your judgment. This template captures common patterns, not rigid rules. Examples of when to diverge:

• Investigation-heavy sessions may need more "Discovery" sections
• Multi-issue sessions may need per-issue subsections
• Planning sessions may emphasize "Design Decisions" over "Implementation"
• Quick fixes may not need full structure (but document them anyway!)

The goal is comprehensive documentation for future sessions, not adherence to a format.

Header Format

# YYYY-MM-DDThh:mm+zzzz (Location) - Brief Title

Required Sections

Overview

High-level summary of what was accomplished. 2-3 sentences capturing the essence.

Purpose: Quick understanding without reading full entry.

Context

Why this work? What's the background?

• Reference Linear issues (BIG-XXX)
• Link to previous sessions if continuing work
• Explain user requests or pain points being addressed

Purpose: Understanding motivation and how this fits into larger picture.

Problem Analysis OR Implementation Approach

For bug fixes:

• Root cause discovery process
• Investigation steps taken
• What was broken and why

For features:

• Architectural decisions
• Approach chosen
• High-level design

Purpose: Understanding the problem space or design approach before diving into code.

Implementation OR Solution

What code changes were made? What was built?

Be specific:

• File changes with line numbers when relevant (e.g., TimelineProcessor.swift:234)
• Key code patterns or algorithms
• Database migrations, schema changes
• Build issues encountered and how fixed
• UI changes with before/after descriptions

Purpose: Detailed record of what was actually changed.

Testing

How was it validated?

Must include:

• On-device testing results (required per version control rules for code changes)
• Specific scenarios tested
• Edge cases verified
• What worked, what didn't
• Performance measurements if relevant

Purpose: Proving the changes work and documenting test coverage.

Design Decisions

CRITICAL SECTION - Document "why X not Y" thinking using this pattern:

#### Why [Decision About What]?
**Considered**: [Alternative approach A]
- Pros: ...
- Cons: ...

**Rejected**: [Reason it didn't work]

**Chosen**: [Approach we took] because:
- [Rationale point 1]
- [Rationale point 2]

Examples of good design decision topics:

• Why this data structure over that one
• Why this API pattern vs alternatives
• Why solve now vs defer
• Why this level of abstraction
• Why this testing approach

Purpose: Future sessions need to understand WHY decisions were made. This is often the most valuable section.

Key Learnings

What did we discover? What would we do differently?

Include:

• Mistakes made and how corrected (be explicit!)
• Unexpected behaviors or patterns discovered
• Things that surprised us
• Better ways to approach similar problems in future
• "If I had to do this again, I would..."

Purpose: Capturing knowledge that prevents repeating mistakes and informs future similar work.

Files Modified

Complete list with repo context.

Format:

**LocoKit2**:
- `Sources/LocoKit2/Models/TimelineItem.swift` - Added preventAutoMerge field
- `Sources/LocoKit2/Database/Database+Schema.swift` - Migration for new column

**Arc Timeline Editor**:
- `Arc Timeline Editor/Views/Timeline/TimelineMap.swift` - Updated gesture handling

Purpose: Quick reference for what changed and where.

Commits

List all commits made, or note if uncommitted with rationale.

Format:

**LocoKit2** (`a1b2c3d`):
- Brief description of commit
- Key changes included

**Arc Timeline Editor** (`d4e5f6g`):
- Brief description

**Uncommitted**: [Explain why - usually waiting for testing or related work]

Purpose: Linking session to git history and documenting commit strategy.

Conditional Sections

Include these when relevant:

Remaining Work

Unfinished tasks, next steps, follow-up items.

Use when:

• Session ended due to context limits mid-task
• Discovered additional work during implementation
• Follow-up tasks identified

Format: Bulleted list with enough detail for next session to pick up.

Open Questions

Things we need to figure out but haven't resolved yet.

Format:

**Question**: [Specific question]

**Context**: Why it matters

**Status**: Not blocking / Blocking for X

Mysteries and Uncertainties

Things we don't understand. Be explicit about unknowns.

Examples:

• Unexpected behavior we observed but couldn't explain
• Performance characteristics we don't understand
• API behaviors that seem inconsistent
• Edge cases we discovered but didn't fully investigate

Purpose: Honest documentation of gaps in understanding. Future sessions may need to investigate these.

References

Linear issues: List with status changes made Related sessions: Link to previous work on same feature Knowledge files: Which ones were read or updated External docs: Links to API docs, blog posts, etc.

Tips for Writing Good Dev Logs

1. Write for your future self: You have no memory between sessions. What context would you need?

2. Document mistakes: Failed approaches are valuable. Future sessions need to know what doesn't work.

3. Be specific: "Fixed the bug" is useless. "Fixed race condition in TimelineObserver by adding 100ms debounce" is useful.

4. Capture "why": Code shows "what", dev logs should show "why".

5. Design Decisions are gold: These age best. Implementation details may change, but decision rationale remains valuable.

6. Don't skip "Mysteries": Unknown behaviors need documentation so future sessions can investigate or work around them.

7. More detail > less detail: 500-line entries are fine. Token efficiency comes from loading only relevant sessions, not skimping on detail.

Section Pattern Analysis

Based on analysis of weeks 39-42 (40+ entries):

Most common sections:

• Files Modified (27 times) - universal
• Overview (26 times) - universal
• Key Learnings (16 times) - very high value
• Commits (16 times) - tracking
• Mysteries and Uncertainties (16 times) - documenting unknowns
• Context/Problem Context (16 times) - motivation
• Design Decisions (10 times) - very high value

Section naming consistency:

• Use "Mysteries and Uncertainties" (not "Mysteries/Uncertainties" or "Mysteries & Uncertainties")
• Use "Key Learnings" (not "Key Learning" or "Learnings")
• Use "Design Decisions" (not "Key Decisions")
• Use "Files Modified" (not "Changed Files" or "Modifications")

devlog_helper.sh

#!/bin/bash

# Dev Log Helper Script
# Gathers information and prompts for details needed for creating per-session dev log entries

# 1. Get current timestamp in ISO format
TIMESTAMP=$(date "+%Y-%m-%dT%H:%M%z")
echo "TIMESTAMP: $TIMESTAMP"

# 2. Get current week number and year
WEEK=$(date "+%V")
YEAR=$(date "+%Y")
echo "WEEK: $WEEK"
echo "YEAR: $YEAR"

# 3. Extract date and time components for filename
FILE_DATE=$(date "+%Y-%m-%d")
FILE_TIME=$(date "+%H%M")
echo "FILE_DATE: $FILE_DATE"
echo "FILE_TIME: $FILE_TIME"

# 4. Define path to current week's directory
LOG_DIR="/Users/matt/Projects/Arc Family/docs/devlogs"
WEEK_DIR="$LOG_DIR/${YEAR}_w${WEEK}"
echo "WEEK_DIR: $WEEK_DIR"

# 5. Create week directory if it doesn't exist
if [ ! -d "$WEEK_DIR" ]; then
    mkdir -p "$WEEK_DIR"
    echo "WEEK_DIR_CREATED: true"
else
    echo "WEEK_DIR_EXISTS: true"
fi

# 6. List existing sessions in current week chronologically
echo "CURRENT_WEEK_SESSIONS:"
if [ -d "$WEEK_DIR" ]; then
    ls -1 "$WEEK_DIR" | while read -r session; do
        echo "  - $session"
    done
fi

# 7. Find most recent previous session (may be in previous week)
LATEST_SESSION=""
# First check current week
if [ -d "$WEEK_DIR" ]; then
    LATEST_SESSION=$(ls -t "$WEEK_DIR" | head -1)
fi
# If current week has sessions, use latest; otherwise check previous weeks
if [ -z "$LATEST_SESSION" ]; then
    # Find all week directories, sort reverse chronologically
    for week_dir in $(ls -dt "$LOG_DIR"/????_w?? 2>/dev/null); do
        if [ -d "$week_dir" ] && [ "$week_dir" != "$WEEK_DIR" ]; then
            LATEST_SESSION=$(ls -t "$week_dir" | head -1)
            if [ -n "$LATEST_SESSION" ]; then
                PREV_SESSION_PATH="$week_dir/$LATEST_SESSION"
                break
            fi
        fi
    done
fi

if [ -n "$LATEST_SESSION" ] && [ -z "$PREV_SESSION_PATH" ]; then
    PREV_SESSION_PATH="$WEEK_DIR/$LATEST_SESSION"
fi

if [ -n "$PREV_SESSION_PATH" ] && [ -f "$PREV_SESSION_PATH" ]; then
    echo "PREVIOUS_SESSION_PATH: $PREV_SESSION_PATH"
    echo "READ_PREVIOUS_SESSION: true"
else
    echo "READ_PREVIOUS_SESSION: false"
fi

# 8. Find same-day sessions (for loading conventions)
echo "SAME_DAY_SESSIONS:"
if [ -d "$WEEK_DIR" ]; then
    ls -1 "$WEEK_DIR" | grep "^${FILE_DATE}" | while read -r session; do
        echo "  - $WEEK_DIR/$session"
    done
fi

# 9. Prompt for session description (interactive)
echo ""
echo "=== Session Details ==="
read -p "Brief description (3-5 words, e.g., 'json-importer-testing'): " DESCRIPTION
# Sanitize: lowercase, spaces to hyphens, remove special chars except hyphens
DESCRIPTION=$(echo "$DESCRIPTION" | tr '[:upper:]' '[:lower:]' | tr ' ' '-' | sed 's/[^a-z0-9-]//g')
echo "DESCRIPTION: $DESCRIPTION"

# 10. Prompt for issue IDs (optional, comma-separated)
read -p "Issue IDs (optional, comma-separated, e.g., 'BIG-196,BIG-198'): " ISSUES
# Sanitize: uppercase, remove spaces, validate format
ISSUES=$(echo "$ISSUES" | tr '[:lower:]' '[:upper:]' | tr -d ' ')
if [ -n "$ISSUES" ]; then
    # Convert comma-separated to underscore-separated
    ISSUES=$(echo "$ISSUES" | tr ',' '_')
    echo "ISSUES: $ISSUES"
    FILENAME="${FILE_DATE}_${FILE_TIME}_${ISSUES}_${DESCRIPTION}.md"
else
    echo "ISSUES: (none)"
    FILENAME="${FILE_DATE}_${FILE_TIME}_${DESCRIPTION}.md"
fi

# 11. Construct full session file path
SESSION_FILE_PATH="$WEEK_DIR/$FILENAME"
echo "SUGGESTED_FILENAME: $FILENAME"
echo "SESSION_FILE_PATH: $SESSION_FILE_PATH"

# 12. Check if suggested filename already exists
if [ -f "$SESSION_FILE_PATH" ]; then
    echo "!! WARNING: File already exists at this path !!"
fi

echo ""
echo "=== Loading Recommendations ==="
echo "LOAD_PREVIOUS: true (always load immediately previous session)"
if [ -n "$(ls -1 "$WEEK_DIR" 2>/dev/null | grep "^${FILE_DATE}")" ]; then
    echo "LOAD_SAME_DAY: true (found other sessions from today)"
fi

echo ""
echo "DEVLOG_HELPER_COMPLETE"

sessionend.md

Session End

Write a development log entry for the completed work session.

Description

Creates a detailed development log entry following the Arc project's per-session file standards, ensuring all work is properly documented. Sessions may end due to task completion, context limits, or natural break points - this command handles all cases.

Command

# Run the devlog helper script to gather all necessary information and prompt for session details
cd "/Users/matt/Projects/Arc Family" && ./devlog_helper.sh

Prompt

I need to write a development log entry for the work session I just completed.

1. CRITICAL AND REQUIRED: First, run the devlog_helper script which will prompt for session details:

   Bash(command: "cd \"/Users/matt/Projects/Arc Family\" && ./devlog_helper.sh", description: "Running devlog helper script")
   

   The script will:

   • Display current timestamp for your log entry header: ## YYYY-MM-DDThh:mm+zzzz (Location)
   • Show existing sessions in current week
   • Identify previous session to load
   • Prompt for brief session description (3-5 words)
   • Prompt for issue IDs if applicable (e.g., BIG-196, BIG-198)
   • Suggest filename following format: YYYY-MM-DD_HHMM_ISSUES_description.md
   • Provide loading recommendations per conventions

   DO NOT invent or guess the timestamp - it must be generated at time of writing.

   For location:

   • Check the timezone in the timestamp against the previous log entry
   • If the timezone is the same (e.g., both +0800), assume the same location unless told otherwise
   • Common locations by timezone:
     • +0800: Bali, Singapore
     • +0700: Bangkok
     • +0900: Tokyo
   • Only ask for location if timezone differs from previous entry or if uncertain

2. Load context following the conventions (see CLAUDE.md "Dev Log Loading Conventions"):

   Always load previous session (script output shows PREVIOUS_SESSION_PATH):

   Read(file_path: "[PREVIOUS_SESSION_PATH from script output]")
   

   Load same-day sessions if working on recent stuff (script shows SAME_DAY_SESSIONS):

   Read(file_path: "[each session path listed]")
   

   Load intervening sessions if continuing work on same issue:

   • Use grep to find all sessions mentioning the issue ID(s)
   • Load all sessions between first and last occurrence chronologically
   • This captures architectural dependencies from intervening work

   Example:

   Bash(command: "grep -l 'BIG-196' /Users/matt/Projects/Arc\\ Family/docs/devlogs/2025_w42/*.md", description: "Find BIG-196 sessions")
   # Then load all sessions between first and last match
   

3. Write the entry following these guidelines:

   • First, read the template: /Users/matt/Projects/Arc Family/docs/knowledge/dev_log_template.md
   • This template codifies patterns from 40+ entries - use it as a guide, not a straitjacket
   • Read through our entire conversation to understand all work completed
   • Document ALL details to facilitate potential handover to a new chat context
   • Include clear descriptions of work completed, key decisions and rationales
   • Document any mistakes made AND how they were corrected
   • Document any mysteries or uncertainties introduced
   • List all files modified
   • Include remaining TODOs or dangling work items
   • Remember more detail is better than less - you have no memory between chat contexts
   • Flexibility: Use additional sections when they make sense for the specific session

4. Format the entry following this structure:

   Header: # YYYY-MM-DDThh:mm+zzzz (Location) - Brief Title

   Required Sections (every entry):

   ## Overview
   High-level summary of what was accomplished. 2-3 sentences capturing the essence.
   
   ## Context
   Why this work? What's the background? Reference Linear issues, previous sessions, or user requests.
   
   ## Problem Analysis OR Implementation Approach
   - For bug fixes: Root cause discovery, investigation process
   - For features: Architectural decisions, approach taken
   - Include "Considered/Rejected/Chosen" patterns for design decisions
   
   ## Implementation OR Solution
   What code changes were made? What was built? Be specific about:
   - File changes with line numbers when relevant
   - Key code patterns or algorithms
   - Build issues encountered and fixed
   
   ## Testing
   How was it validated? Include:
   - On-device testing results (required for code changes per version control rules)
   - Edge cases tested
   - What worked, what didn't
   
   ## Design Decisions
   Critical section! Document "why X not Y" thinking:
   - **Considered**: Alternative approaches
   - **Rejected**: Why they didn't work
   - **Chosen**: Rationale for the approach taken
   Use this format for significant decisions.
   
   ## Key Learnings
   What did we discover? Include:
   - Mistakes made and how corrected
   - Unexpected behaviors or patterns
   - Things that surprised us
   - Better ways to approach similar problems in future
   
   ## Files Modified
   Complete list with repo context (LocoKit2 vs Arc Timeline Editor)
   
   ## Commits
   Include commit hashes and messages (or note if uncommitted with rationale)

   Conditional Sections (include when relevant):

   ## Remaining Work
   Unfinished tasks, next steps, follow-up items
   
   ## Open Questions
   Things we need to figure out but haven't yet
   
   ## Mysteries and Uncertainties
   Things we don't understand. Be explicit about unknowns.
   
   ## References
   Linear issues (with status updates), related dev log entries, knowledge files, external docs

5. Create the new session file:

   • Use the SESSION_FILE_PATH from devlog helper script output
   • Write the complete entry to that path
   • DO NOT append to a weekly file - each session gets its own file

6. After creating the entry:

   • Review and UPDATE the following files based on our work session (take ownership, don't just suggest):
     • Relevant knowledge base sections in /Users/matt/Projects/Arc Family/docs/knowledge/
     • Project manifests at:
       • /Users/matt/Projects/Arc Family/docs/Arc-Editor/arc_manifest.md
       • /Users/matt/Projects/Arc Family/docs/LocoKit2/locokit2_manifest.md
   • Knowledge files exist purely for AI consumption - update them proactively to document:
     • New patterns discovered
     • Architectural decisions and rationales
     • Common pitfalls and solutions
     • Implementation examples
   • Create new knowledge files if needed for significant new patterns
   • These are YOUR documentation for future sessions - maintain them actively

Important Notes

• Session vs Task: Sessions end for various reasons - task completion, context limits, natural break points. The dev log should document the work completed in the session, not necessarily a complete task.
• Multiple Issues: Sessions may touch multiple issues. Include all relevant issue IDs in the filename (comma-separated in prompt, underscore-separated in filename).
• No Issue Sessions: Some sessions (like planning, discussion, tooling updates) may not have Linear issues. That's fine - omit the issue portion of the filename.
• Same-Day Sessions: If this is the 2nd/3rd/etc session today, previous session will be from earlier today. Load all same-day sessions for dense context.