Session Context Management

Auto-activate when: Working with CURRENT.md, STATUS.md, LESSONS.md, .session/ directory, or when user mentions /snapshot, /pickup, resume, session, or context management.

Purpose: Maintain "just enough" context across work sessions for resuming non-trivial development tasks

Philosophy: Document to resume work, not to create archives. Tokens aren't free. Err on side of less.

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When to Activate

Activate this skill when ANY of these are true:

1. Task duration: Work will take more than 15 minutes
2. Multiple files/steps: Work touches 3+ files OR has 3+ distinct steps
3. Interruptions likely: Meeting soon, end of day approaching, or working on unfamiliar code
4. Scope might expand: Starting with "just a quick fix" on complex code
5. User explicitly invokes /snapshot or /pickup commands

Default rule: If unsure whether to activate → activate (overhead is minimal).

Do NOT activate for: Single file edits under 10 minutes, trivial tasks, purely informational requests.

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Core Principles & Anti-Patterns

✅ Do:

• "Just Enough" > Complete - Document to resume, not archive
• Tokens Aren't Free - Every line costs tokens
• User Can Fill Gaps - They remember context better than docs
• Err on Side of Less - Add detail only when painful without it
• ADHD-Friendly - Interruptions and rabbit holes are normal
• Walk Away Anytime - Never lose context mid-work

❌ Don't:

• Complete audit trails - Not an archive
• Explaining obvious things - User knows context
• Upfront planning - Document as you go
• Perfect grammar - Bullets > prose
• Waiting for session end - Update continuously
• Rigid templates - Adapt to needs

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Security Rules (BLOCKING)

CRITICAL: Validate content before writing session files

Before writing to CURRENT.md, STATUS.md, or LESSONS.md, scan content for sensitive data. If detected, REFUSE to write and warn user.

Prohibited Patterns (BLOCK & REFUSE):

• API keys: API_KEY=, sk-ant-, sk-proj-, ANTHROPIC_API_KEY=
• Passwords: PASSWORD=, pwd=, passwd=, password:
• Tokens: TOKEN=, Bearer, token:, access_token=
• Private keys: -----BEGIN PRIVATE KEY-----, -----BEGIN RSA
• Credentials: connection strings with passwords, username/password pairs
• PII: SSN, credit cards, personal email addresses in creds
• CUI: classified info, proprietary secrets

Safe Content (ALLOW):

• Timestamps: 2025-01-13 14:30
• Task descriptions: "Implement login", "Fix auth bug"
• Test results: "3 pass, 1 fail", "Coverage 85%"
• Status: "Blocked on API", "Waiting for review"
• Patterns: "Use uv run python", "Prefer Edit over Write"
• File paths: ALWAYS use relative paths (src/auth/login.py) NEVER absolute paths (C:\Users...)

Validation Process:

1. Review entire content block before writing
2. Check for prohibited patterns
3. If found: STOP, show detected content, refuse to write
4. If clean: Proceed with write

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Low Context Warning Protocol

Automatic Monitoring: Check token budget in <system-reminder> tags throughout conversation.

When < 10% Remaining (~<20k tokens):

1. Capture snapshot immediately using CURRENT.md format
2. Alert user: "⚠️ Context usage at [X%] ([used]/[total] tokens). Recommend /clear soon to avoid interruption."
3. Provide resume prompt:

   Copy this to resume after /clear:
   
   Resume [feature-name]: [Right Now from CURRENT.md]
   Last done: [Last item from Done list]
   Next: [Next 3 #1]
   [Blockers if any]
   

When < 5% Remaining (~<10k tokens):

1. Urgent snapshot capture
2. Strong warning: "🚨 Context critical - [remaining] tokens left. /clear now recommended to avoid interruption."
3. Provide ready-to-use resume prompt

Why this approach: No waiting for context compaction, seamless continuation, user control, preserves work.

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File Structure

project-root/
└── .session/feature/[feature-name]/
    ├── CURRENT.md    # 🚀 READ FIRST - Quick resume (~150 lines max, includes Feature Overview)
    ├── STATUS.md     # 📋 Terse log - Chronological entries with discussion capture
    └── LESSONS.md    # 💡 Bullet points - What worked/didn't

Why .session/: Usually gitignored (working memory, not documentation), UNLESS project has enable-session-commits: true

Why feature/[feature-name]/: Separate contexts for different work streams

CURRENT.md structure: Feature Overview (slower-changing 50,000-foot view) + session work state (faster-changing tasks/progress)

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Multi-Instance Support

Scenario: Multiple Claude instances working on same feature simultaneously

Solution: Tagged sections in single files using [instance-id:session-id] format

Instance/Session ID Detection

Instance ID (which IDE window):

INSTANCE_ID=$(cat ~/.claude/ide/$CLAUDE_CODE_SSE_PORT.lock 2>/dev/null | python -c "import json, sys; print(json.load(sys.stdin)['authToken'][:8])" 2>/dev/null || echo "unknown")

Session ID (which conversation):

SESSION_ID=$(ls -lt ~/.claude/debug/*.txt 2>/dev/null | head -1 | awk '{print $9}' | xargs basename 2>/dev/null | cut -d. -f1 | cut -c1-8 || echo "unknown")

Combined Tag: [$INSTANCE_ID:$SESSION_ID] (e.g., [5d72a497:888cf413])

File Format with Multiple Instances

CURRENT.md (shared Feature Overview + separate sections per instance):

# [Feature Name] - Current State

## Feature Overview
**Goal**: High-level description of what this feature accomplishes and why it's needed

**Key Requirements**:
- Critical constraints or dependencies

**User Stories**:
- Specific use cases or scenarios

**Design Decisions**:
- Architectural choices made and their rationale

---

## [5d72a497:888cf413] Frontend Queue
Last: 2025-11-13 23:30

### Right Now
Working on queueing multiple questions without waiting

### Last 5 Done
1. ✅ Implemented queue system
...

---

## [a08428d4:3e5380bd] Transcripts
Last: 2025-11-13 23:28

### Right Now
Adding timestamp support to archive format

### Last 5 Done
1. ✅ Fixed quotes escaping
...

STATUS.md (tagged entries with discussion capture):

# Status Log

---

## [5d72a497:888cf413] 2025-11-13 23:30 - Queue system
**User Request**: Enable submitting multiple questions without blocking
**Discussion**: Chose client-side queue over server queue for simpler implementation
**Outcomes**:
✅ Frontend can queue multiple questions
❌ No concurrent request handling yet
**Next**: Test concurrent requests

---

## [a08428d4:3e5380bd] 2025-11-13 23:28 - Transcript timestamps
**User Request**: Add timing information to transcripts
**Discussion**: Archive format needs extension for metadata
**Outcomes**:
❌ Timestamps not in archive format
**Next**: Add timing metadata

LESSONS.md (shared, no tags):

• No instance tags - shared learnings across all instances working on feature

Behavior

• Each /snapshot updates or creates its own [instance:session] section
• Other instances' sections preserved
• /pickup shows all instances for all features
• Single source of truth per feature, multiple contexts visible

---

File Format Templates

CRITICAL: Use Relative Paths Only

When writing file paths in session files, ALWAYS use relative paths from the feature's working directory:

• ✅ GOOD: frontend/src/routes/+page.svelte, api/main.py, docker-compose.yml
• ❌ BAD: C:\Projects\agent-spike\projects\mentat\api\main.py, projects/mentat/frontend/src/...
• ❌ BAD: /home/user/code/app/main.py

Rationale:

• Session files may be shared or moved
• Absolute paths expose system details and break portability
• Paths relative to feature directory are most natural when working in that context
• Example: .session/feature/mentat/ should use api/main.py not projects/mentat/api/main.py

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CURRENT.md - Quick Resume with Feature Overview

Purpose: Resume work in < 2 minutes | Max Size: 150 lines | Update: After milestones (1-2 hours work)

Structure: Feature Overview (slower-changing) at top, session work state (faster-changing) below

# [Feature Name] - Current State

## Feature Overview
**Goal**: [What this feature accomplishes and why it's needed - 50,000-foot view]

**Key Requirements**:
- [Critical constraints, dependencies, or technical requirements]
- [Another key requirement]

**User Stories**:
- [Specific use case or user scenario]
- [Another user story]

**Design Decisions**:
- [Architectural choice made]: [Rationale]
- [Another design decision]: [Why this approach]

---

## [instance-id:session-id] [Session Title]
Last: YYYY-MM-DD HH:MM

### Right Now
[One sentence describing what you're doing RIGHT NOW]

### Last 5 Done
1. ✅ [Most recent completed task]
2. ✅ [Previous completed task]
3. ✅ [Earlier completed task]
4. ✅ [Earlier completed task]
5. ✅ [Earliest completed task]

### In Progress
[If TodoWrite active: Copy active todos here]
[If no TodoWrite: List what's being worked on from context]
- [Active item 1]
- [Active item 2]

### Paused
[Leave empty UNLESS you context-switched to different feature]
[If paused items exist: "- [Feature name] - [Why paused]"]

### Tests
[If tests were run, show results. If not run yet, write "Not run yet"]
**[Framework name]**: X pass / Y fail
- ❌ [failing-test-name] - [why it's failing]

### Blockers
[List specific blockers OR write "None"]

### Next 3
1. [The immediate next action - be specific]
2. [Then do this]
3. [After that]

---
Details → STATUS.md

Feature Overview Guidelines:

• Slower-changing: Only update when feature scope/understanding evolves
• 50,000-foot view: High-level context, not implementation details
• Concise: Each section should be bullets or short sentences
• Backward compatible: Existing sessions without overview still work
• Created on first snapshot: Inferred from conversation or prompted from user
• Shared across instances: All instances working on same feature see same overview

STATUS.md - Terse Log with Discussion Capture

Purpose: Chronological breadcrumbs with context | Size: No limit, but keep entries SHORT | Update: After meaningful steps

# Status Log

[Append-only log - oldest to newest]

---

## [instance:session] YYYY-MM-DD HH:MM - [What we did]
**User Request**: [Summarized intent of user's request]
**Discussion**: [Key decisions, alternatives considered, trade-offs - omit if obvious]
**Outcomes**:
✅/❌ [Outcome]
**Next**: [Action]

---

[Keep entries SHORT - this is breadcrumbs, not a diary]
[Discussion field captures "why" for important decisions]

Good example with discussion:

## [5d72:888c] 2025-01-12 14:35 - Login page
**User Request**: Add certificate and credential authentication
**Discussion**: Chose dual auth over single method for flexibility
**Outcomes**:
✅ Cert & cred auth working
❌ Cookies broken in tests
**Next**: Fix playwright config

Good example without discussion (routine work):

## [5d72:888c] 2025-01-12 15:10 - Fix tests
**User Request**: Fix broken cookie tests
**Outcomes**:
✅ Playwright config updated
✅ All tests passing
**Next**: Deploy to staging

LESSONS.md - Bullet Points

Purpose: Extract patterns that worked/didn't | Update: After completing features | Format: Bullets, not essays

# Lessons Learned

[Organized by category, not chronologically]

---

## [Feature/Category]

### Pattern: [Name]
- Context: [Why we needed this]
- Solution: [What worked] → [relative/path/to/file:line]
- Gotcha: [What tripped us up]
- Use when: [Future scenarios]

---

[KEEP IT BULLETS - No essays. Only write what you'll reference again.]

Rule: If you won't reference it again, don't write it.

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Workflow

Session Start (Claude):

1. Read CURRENT.md (< 1 min)
2. Say: "Resuming: [Right Now]. Next: [Next 3 #1]"
3. Mention blockers if any
4. Start work

During Work (Claude):

1. Work on task
2. Update CURRENT.md after milestones
3. Append to STATUS.md (terse!)
4. User can walk away anytime

Context Switch (Rabbit Hole):

1. Move current work to "Paused"
2. Update "Right Now" with new focus
3. Work on new thing
4. Resume later from CURRENT.md

Feature Complete:

1. Mark in CURRENT.md
2. Final STATUS.md entry
3. Extract bullets to LESSONS.md
4. Update "Next 3"
5. Archive session: Auto-suggest moving to .session/completed/[feature-name]
   • Offer to execute: mv .session/feature/[name] .session/completed/[name]
   • Ask for confirmation before archiving

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Snapshot Creation (Manual /snapshot Command)

Purpose: Manual failsafe for capturing state before interruptions, reboots, context switches, or risky work.

When to Snapshot: Before system reboots, meetings/interruptions, context switches, risky refactoring, end of work day, or any time user requests /snapshot

High-Level Process:

1. Check git tracking policy (see Activation Instructions for logic)
2. Validate feature-name - No /, \, or special chars. Sanitize if needed, ask user to confirm.
3. Create directory: mkdir -p ".session/feature/<feature-name>"
4. Create/Overwrite CURRENT.md with exact template structure above (populate with current state)
5. Append to STATUS.md with timestamp and outcome (create if missing with header)
6. Create LESSONS.md if missing (never modify if exists - human-curated only)
7. Verify all 3 files exist: test -f each file
8. Show confirmation: ls -lh directory and report sizes

Fill CURRENT.md with:

• Timestamp (YYYY-MM-DD HH:MM)
• Right Now: One sentence what you're doing
• Last 5 Done: From conversation/TodoWrite
• In Progress: Copy active todos or current work items
• Paused: Only if context-switched
• Tests: Results if run, else "Not run yet"
• Blockers: Specific blockers or "None"
• Next 3: Immediate next actions

Append to STATUS.md:

• Timestamp + brief description
• ✅ What succeeded
• ❌ What failed/incomplete
• Next: What should happen next

Error Handling:

• mkdir fails: Report error, check permissions
• Feature name invalid: Sanitize, ask user to confirm
• .session is file not directory: Report error, ask user to resolve
• Verification fails: Attempt recreate, report which files succeeded/failed
• Never claim success without verification

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Pickup/Resume (Manual /pickup Command)

Purpose: Resume work from a saved session.

High-Level Process:

1. Check git tracking policy (see Activation Instructions for logic)
2. Read CURRENT.md - Extract: "Right Now", "Last 5 Done" #1, "Blockers", "Next 3" #1
   • If missing: List available sessions, ask which to resume, STOP
3. Read STATUS.md - Show last 2-3 entries (timestamp + outcome)
   • If missing: Skip (no error)
4. Check LESSONS.md - If STATUS entries ≥5 and LESSONS empty/missing, remind user to document patterns
5. Display resume format:

   Resuming [feature-name]: [Right Now]
   
   Last done: [Item #1 from Last 5 Done]
   
   [If STATUS.md exists:]
   Recent work:
   - [Timestamp] [Outcome summary]
   - [Timestamp] [Outcome summary]
   
   Next: [Item #1 from Next 3]
   
   [If blockers:]
   ⚠️ Blockers: [Blockers]
   
   [If LESSONS reminder needed:]
   💡 Consider documenting patterns in LESSONS.md
   

6. Begin work immediately - Execute "Next 3 #1" action, don't ask what to do

Error Handling:

• Session directory doesn't exist: List available, ask which to resume
• CURRENT.md missing: Report error, offer to create new or pick different session
• CURRENT.md malformed: Read what's available, warn about missing sections

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Activation Instructions

When task meets criteria OR /snapshot//pickup invoked:

1. Check git tracking policy (MUST do FIRST before creating session files):

   Step 1a: Check if .claude/CLAUDE.md exists in project root

   • Run: test -f .claude/CLAUDE.md

   Step 1b: If .claude/CLAUDE.md exists, search for session commit setting

   • Use Grep tool: Search for pattern enable-session-commits:\s*true in .claude/CLAUDE.md
   • This is a SIMPLE grep search - just look for the exact line

   Step 1c: Apply policy based on search result

   • IF "enable-session-commits: true" FOUND:

     • Session files WILL be committed to git
     • SKIP all gitignore steps
     • DO NOT modify .gitignore
     • DO NOT add .session/ to gitignore
     • Session files are TRACKED

   • IF "enable-session-commits: true" NOT FOUND (or .claude/CLAUDE.md doesn't exist):

     • Session files should NOT be committed
     • Check if .gitignore exists: test -f .gitignore
     • If .gitignore exists: Read and check for .session/ line. Add if missing under "Session-specific directories" section.
     • If .gitignore missing: Create with minimum content:

       # Session-specific directories
       .session/
       

     • Why: Prevents accidental commits of session working memory

2. Create structure: .session/feature/[feature-name]/

3. Initialize files: CURRENT.md, STATUS.md, LESSONS.md (see templates above)

4. Tell user: "Session context tracking active for [feature-name]"

5. Update frequently: After milestones, stay terse, monitor token budget

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Self-Evaluation

Every 5-10 features, review and ask:

1. Did we document TOO MUCH? - Walls of text nobody reads? Sections never referenced?
2. Did we document TOO LITTLE? - Couldn't resume work? Lost important "why"?
3. Token efficiency? - Documentation vs actual work ratio. Can we be more terse?
4. What sections matter? - Which parts actually used?

Goal: Continuous improvement toward "just enough"

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Success Criteria

✅ Resume work in < 2 minutes from cold start ✅ CURRENT.md stays under ~100 lines ✅ STATUS.md entries are terse (< 50 words) ✅ Can walk away anytime without loss ✅ Find "why" in < 3 minutes when needed ✅ Token usage is efficient ✅ Self-evaluation shows we err on "less"

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Integration with Other Skills

Works alongside:

• testing-workflow - Test results in CURRENT.md
• git-workflow - Commit SHAs in STATUS.md if relevant
• python-workflow / web-projects - Same context system

This skill provides working memory. Other skills provide domain knowledge.