Our review
Cortex is a persistent cognitive layer for Claude Code that stores, queries, and reasons about memories across sessions.
Strengths
- Persistent memory across Claude Code sessions
- Simple command-line interface with visual feedback
- Deep reasoning capabilities (reflection, inference) beyond simple memorization
- Export memories as JSON or Markdown
Limitations
- API costs associated with reasoning operations (approximately $0.01 per reflection)
- Requires the Cortex MCP server to be configured
- Memory consolidation can be expensive ($0.02)
Use Cortex when working on complex projects where contextual memory and cross-session learnings are vital for productivity.
Avoid Cortex for simple, one-off tasks where cross-session memory is unnecessary, to save on API costs.
Security analysis
SafeThe skill only instructs the use of MCP memory tools (cortex__query, cortex__reflect, etc.) and reads/writes local files in ~/.claude/memory/. There are no destructive operations, no remote code execution, no exfiltration of secrets, and no obfuscated payloads.
No concerns found
Examples
What did I do last time in this project?Remember: always validate JWT tokens before processing requests.How does the caching mechanism connect to the authentication system?Cortex - Claude's Cognitive Layer
Metadata
name: cortex description: Cross-session memory with deep reasoning - query, reflect, learn, consolidate version: 2.0.0 triggers:
- /cortex
- memory
- remember
- what did I do
- past sessions
- learnings
Overview
Cortex provides persistent memory across Claude Code sessions. This skill exposes the Cortex MCP tools as user-friendly commands with visual feedback.
Commands
| Command | Description | Cost |
|---------|-------------|------|
| /cortex | Show status and available commands | Free |
| /cortex help | Show detailed help with examples | Free |
| /cortex query <search> | Search stored memories | ~$0.001 |
| /cortex recall | Get context-aware memories for current task | ~$0.001 |
| /cortex reflect <topic> | Deep meta-cognitive analysis | ~$0.01 |
| /cortex infer <concepts> | Find connections between ideas | ~$0.01 |
| /cortex learn <insight> | Store a new learning | ~$0.01 |
| /cortex consolidate | Clean up and organize memories | ~$0.02 |
| /cortex stats | Show memory counts and API costs | Free |
| /cortex health | Verify all systems are working | Free |
| /cortex log | View recent activity log | Free |
| /cortex config | View/edit configuration | Free |
| /cortex export [format] | Export memories (json/md) | Free |
| /cortex session | Show current session summary | Free |
Visual Feedback
When Cortex processes, display neural activity:
╭──────────────────────────────────╮
│ 🧠 CORTEX ══════════════════════│
│ · ∿ · ∿ · ∿ · │
│ ◇━━━◇━━━◇ ◆━━━◆━━━◆ │
│ Haiku Sonnet │
│ querying... │
╰──────────────────────────────────╯
Instructions
When the user invokes /cortex or asks about memories/past sessions:
0. Help Command (/cortex help)
Display comprehensive help with groupings:
╭─────────────────────────────────────────────────╮
│ 🧠 CORTEX v2.0 - Claude's Memory Layer │
├─────────────────────────────────────────────────┤
│ QUICK │
│ /cortex Status overview │
│ /cortex help This screen │
│ /cortex stats Memory counts & costs │
│ /cortex health Verify everything works │
│ │
│ MEMORY (Haiku - fast, ~$0.001) │
│ /cortex query "X" Search memories │
│ /cortex recall Context retrieval │
│ │
│ REASONING (Sonnet - deep, ~$0.01) │
│ /cortex reflect "X" Meta-analysis │
│ /cortex infer A B Find connections │
│ /cortex learn "X" Store insight │
│ /cortex consolidate Clean up │
│ │
│ UTILITIES │
│ /cortex log Recent activity │
│ /cortex config View/edit settings │
│ /cortex export Export memories │
│ /cortex session Current session info │
│ │
│ NATURAL LANGUAGE │
│ "What did I do last time?" │
│ "Remember: always validate JWT first" │
│ "What patterns am I seeing?" │
│ "How does X connect to Y?" │
╰─────────────────────────────────────────────────╯
1. Status Command (/cortex or /cortex status)
Display current Cortex status:
╭─────────────────────────────────────────────╮
│ 🧠 CORTEX STATUS │
├─────────────────────────────────────────────┤
│ MCP Server: ✓ Connected │
│ Memories: 127 total │
│ • Skills: 23 │
│ • Patterns: 34 │
│ • Learnings: 45 │
│ • Insights: 25 │
│ Last Activity: 2 hours ago │
│ Session Cost: $0.02 │
╰─────────────────────────────────────────────╯
To get this data:
- Count lines in
~/.claude/memory/data/memories/*.jsonl - Check
~/.claude/memory/logs/for last activity - Read stats from MCP server if available
2. Query Command (/cortex query <search>)
╭──────────────────────────────────────╮
│ 🧠 CORTEX ═══════════════════════ │
│ · ∿ · ∿ · │
│ ◇━━━◇━━━◇ Haiku searching... │
╰──────────────────────────────────────╯
Use the cortex__query MCP tool with the search term.
Display results with relevance scores.
3. Reflect Command (/cortex reflect <topic>)
╭──────────────────────────────────────╮
│ 🧠 CORTEX ═══════════════════════ │
│ · ∿ · ∿ · │
│ ◆━━━◆━━━◆ Sonnet thinking...│
╰──────────────────────────────────────╯
Use the cortex__reflect MCP tool. This uses Sonnet for deep reasoning.
Include depth parameter: quick (512 tokens), moderate (1024), deep (2048).
4. Learn Command (/cortex learn <insight>)
╭──────────────────────────────────────╮
│ 🧠 CORTEX ═══════════════════════ │
│ · ∿ · ∿ · │
│ ◆━━━◆━━━◆ Sonnet analyzing..│
╰──────────────────────────────────────╯
Use the cortex__learn MCP tool to store the insight.
Report quality score and whether it was stored.
5. Stats Command (/cortex stats)
Read and display:
- Memory file sizes and counts
- API token usage from server stats
- Estimated costs (Haiku: $0.25/1M, Sonnet: $3/1M)
╭─────────────────────────────────────────────╮
│ 🧠 CORTEX STATS │
├─────────────────────────────────────────────┤
│ MEMORIES │
│ Skills: 23 entries (12 KB) │
│ Patterns: 34 entries (8 KB) │
│ Learnings: 45 entries (15 KB) │
│ Insights: 25 entries (6 KB) │
│ ───────────────────────────────── │
│ Total: 127 entries (41 KB) │
├─────────────────────────────────────────────┤
│ API USAGE (This Session) │
│ Haiku: 1,234 tokens ~$0.0003 │
│ Sonnet: 5,678 tokens ~$0.017 │
│ ───────────────────────────────── │
│ Total Cost: ~$0.02 │
╰─────────────────────────────────────────────╯
6. Health Command (/cortex health)
Run comprehensive health check:
╭─────────────────────────────────────────────────╮
│ 🧠 CORTEX HEALTH CHECK │
├─────────────────────────────────────────────────┤
│ MCP Server ✓ Connected │
│ Memory Files ✓ 5 files (127 entries) │
│ API Key ✓ Valid (sk-ant-...) │
│ Hooks ✓ SessionStart, SessionEnd │
│ Last Activity 2 hours ago │
│ Disk Usage 41 KB │
├─────────────────────────────────────────────────┤
│ STATUS: All systems operational ✓ │
╰─────────────────────────────────────────────────╯
To verify:
- Check MCP connection:
claude mcp list | grep cortex - Check files exist:
ls ~/.claude/memory/data/memories/ - Check API key:
[ -n "$ANTHROPIC_API_KEY" ] && echo "Set" - Check hooks:
grep -A3 "SessionStart" ~/.claude/settings.json
7. Log Command (/cortex log)
Show recent activity from logs:
╭─────────────────────────────────────────────────╮
│ 🧠 CORTEX ACTIVITY LOG (last 10) │
├─────────────────────────────────────────────────┤
│ 14:32 query "authentication" → 3 hits │
│ 14:28 learn "JWT pattern" → stored │
│ 14:15 recall (session start) → 2 items │
│ 13:45 reflect "debugging approach" → complete│
│ ... │
╰─────────────────────────────────────────────────╯
Read from: ~/.claude/memory/logs/*.log
8. Config Command (/cortex config)
Show current configuration:
╭─────────────────────────────────────────────────╮
│ 🧠 CORTEX CONFIGURATION │
├─────────────────────────────────────────────────┤
│ SESSION START │
│ Max memories injected: 5 │
│ Relevance threshold: 0.3 │
│ │
│ SESSION END │
│ Quality threshold: 0.4 │
│ Max extractions: 10 │
│ │
│ LADS (Learning) │
│ Evolution enabled: yes │
│ Evolution interval: 24h │
│ │
│ Config file: ~/.claude/memory/data/configs/ │
│ current.json │
╰─────────────────────────────────────────────────╯
Read from: ~/.claude/memory/data/configs/current.json
9. Export Command (/cortex export [format])
Export memories to file:
/cortex export # Default: markdown
/cortex export json # JSON format
/cortex export md # Markdown format
Output example for markdown:
# Cortex Memory Export
Generated: 2026-01-27
## Skills (23 entries)
- Authentication: Use JWT with refresh tokens...
- Error handling: Always log context...
## Learnings (45 entries)
- "Always validate JWT expiry before permissions"
- "Use circuit breaker for external API calls"
...
10. Session Command (/cortex session)
Show current session summary:
╭─────────────────────────────────────────────────╮
│ 🧠 CORTEX SESSION │
├─────────────────────────────────────────────────┤
│ Started: 14:00 (2h 32m ago) │
│ Working Dir: ~/.claude/memory │
│ Git Branch: master │
│ │
│ INJECTED AT START │
│ • JWT authentication pattern │
│ • Error handling best practices │
│ │
│ WILL EXTRACT AT END │
│ • MCP Resources implementation approach │
│ • Skill enhancement patterns │
│ │
│ API Usage: ~$0.02 │
╰─────────────────────────────────────────────────╯
This shows what memories were injected at session start and previews what will be extracted at session end.
Auto-Activation
This skill should auto-activate when the user says:
- "What did I do last time?"
- "Do you remember when..."
- "Check my past sessions"
- "What have I learned about..."
- "Search my memories for..."
When auto-activated, show the visual feedback and use the appropriate tool.
Error Handling
If MCP server is not connected:
╭──────────────────────────────────────╮
│ 🧠 CORTEX ═══════════════════════ │
│ ✗ MCP Server Not Connected │
│ │
│ Try: claude mcp list │
│ Check: ~/.claude.json │
╰──────────────────────────────────────╯
Examples
User: /cortex query authentication
Response: Shows neural animation, then displays matching memories about authentication patterns.
User: "What approach did I use for the login system?" Response: Auto-activates, queries memories, shows relevant past decisions.
User: /cortex learn "Always validate JWT expiry before checking permissions"
Response: Analyzes insight quality, stores if good, reports result.
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