Session Summarizer

Overview

Every session generates knowledge: decisions made, patterns that worked, problems encountered, questions that arose. Session summaries capture this for future compound learning.

Core principle: Document sessions to build knowledge that compounds across time.

When to Use

User runs /summarize command to create a session summary.

Create summaries to capture:

• What worked and why

• What didn't work and why

• Questions encountered

• Patterns to remember

• Context for future sessions

Information Sources (Required)

You MUST integrate all three sources:

Session logs: ~/.claude/projects/[project-path]/[session-id]/session-memory/summary.md

• Contains context, decisions, learnings that commit messages miss

• Read this FIRST before writing summary

Git history: git log --oneline -n 20 and git diff since session start

• What actually changed

• Commit messages and patterns

Conversation context: Your memory of the session

• Questions asked, approaches tried, decisions made

Using session logs:

Find current session log

ls -la ~/.claude/projects/$(pwd | sed 's//Users/[^/]/Projects///g')//session-memory/summary.md | tail -1

Read it

cat [path-from-above]

Summary Structure

Session Summary - [Date]

Context

[One-line: what was the goal/problem]

Victories

• [What worked, solutions found]
• [Patterns that were effective]

Failures

• [What didn't work, why]
• [Dead ends, wrong assumptions]

Root Causes

• [For each failure above: What in your system prompt or tooling made you make this mistake?]
• [Analyze prompt assumptions, tool limitations, missing context that led to errors]
• [Example: "Assumed Write tool would create parent directories - tooling doesn't support this"]
• [Example: "System prompt emphasized speed over verification - led to skipping file reads"]

Tough Questions

• [Questions that came up, answered or not]
• [Ambiguities encountered]

Improvements

• [What could be better next time]
• [Patterns to codify, failures to document]

Git Activity

• [Commit count, key changes]
• [Files modified, tests added]

Next Session

• [Unfinished items, follow-ups needed]

Workflow

• User runs /summarize command

• Read session logs at ~/.claude/projects/.../summary.md

• Check git log and git diff

• Write structured summary integrating all three sources

• For each failure, analyze root causes in system prompt/tooling

• Ask user if they want summary saved anywhere specific

Root Cause Analysis

For each failure or mistake documented:

• What in the system prompt made you assume something incorrect?

• What tool limitations were you unaware of?

• What context was missing that would have prevented the error?

Examples:

• "Assumed Edit tool would preserve formatting - tool doesn't guarantee this"

• "System prompt didn't mention needing parent directories - led to Write failures"

• "Believed git hooks were disabled by default - prompt never specified"

Purpose: Understand what gaps in prompts or tooling cause errors, enabling systemic improvements.

Example

User: /summarize

You: "I'll create a session summary capturing what we accomplished and learned today."

[Read session logs, check git, write summary with root cause analysis...]

You: "Here's the summary:

Session Summary - 2025-01-18

Context

Fixed authentication bug in React app where tokens weren't persisting across page refreshes.

Victories

• Identified root cause in localStorage timing

• Implemented useEffect hook with proper dependencies

• All tests pass, authentication now persists correctly

Failures

• Initially tried sessionStorage (wrong storage type)

• First useEffect implementation had dependency array issues causing infinite loops

Root Causes

• sessionStorage attempt: System prompt didn't emphasize localStorage vs sessionStorage differences - I assumed sessionStorage would persist but it's page-scoped only

• useEffect infinite loop: Tool limitations - no linter feedback in Edit tool, had to discover through testing rather than static analysis

Tough Questions

• Should tokens go in httpOnly cookies instead of localStorage? (security trade-off)

Improvements

• Add localStorage persistence patterns to project documentation

• Consider adding ESLint rules for useEffect dependencies

Git Activity

• 3 commits

• Modified: src/hooks/useAuth.ts, src/components/Login.tsx

• Added: tests for token persistence

Next Session

• Consider cookie-based auth implementation for better security

Would you like me to save this anywhere specific, or is the session log sufficient?"