claude-mem/cursor-hooks/CONTEXT-INJECTION.md

Context Injection in Cursor Hooks

The Solution: Auto-Updated Rules File

Context is automatically injected via Cursor's Rules system:

1. Install: claude-mem cursor install creates initial context file
2. Stop hook: session-summary.sh updates context after each session ends
3. Cursor: Automatically includes .cursor/rules/claude-mem-context.mdc in all chats

Result: Context appears at the start of every conversation, just like Claude Code!

How It Works

Installation Creates Initial Context

claude-mem cursor install

This:

1. Copies hook scripts to .cursor/hooks/
2. Creates hooks.json configuration
3. Fetches existing context from claude-mem and writes to .cursor/rules/claude-mem-context.mdc

Context Updates at Three Points

Context is refreshed three times per session for maximum freshness:

1. Before prompt submission (context-inject.sh): Ensures you start with the latest context from previous sessions
2. After summary completes (worker auto-update): Immediately after the summary is saved, worker updates the context file
3. After session ends (session-summary.sh): Fallback update in case worker update was missed

Before Prompt Hook Updates Context

When you submit a prompt, context-inject.sh:

# 1. Ensure worker is running
ensure_worker_running "$worker_port"

# 2. Fetch fresh context
context=$(curl -s ".../api/context/inject?project=...")

# 3. Write to rules file (used immediately by Cursor)
cat > .cursor/rules/claude-mem-context.mdc << EOF
---
alwaysApply: true
---
# Memory Context
${context}
EOF

Stop Hook Updates Context

After each session ends, session-summary.sh:

# 1. Generate session summary
curl -X POST .../api/sessions/summarize

# 2. Fetch fresh context (includes new observations)
context=$(curl -s ".../api/context/inject?project=...")

# 3. Write to rules file for next session
cat > .cursor/rules/claude-mem-context.mdc << EOF
---
alwaysApply: true
---
# Memory Context
${context}
EOF

The Rules File

Located at: .cursor/rules/claude-mem-context.mdc

---
alwaysApply: true
description: "Claude-mem context from past sessions (auto-updated)"
---

# Memory Context from Past Sessions

[Your context from claude-mem appears here]

---
*Updated after last session.*

Update Flow

Context updates at three points:

Before each prompt:

1. User submits a prompt
2. beforeSubmitPrompt hook runs context-inject.sh
3. Context file refreshed with latest observations from previous sessions
4. Cursor reads the updated rules file

After summary completes (worker auto-update):

1. Summary is saved to database
2. Worker checks if project is registered for Cursor
3. If yes, immediately writes updated context file with new observations
4. No hook involved - happens in the worker process

After session ends (fallback):

1. Agent completes (loop ends)
2. stop hook runs session-summary.sh
3. Context file updated (ensures nothing was missed)
4. Ready for next session

Project Registry

When you run claude-mem cursor install, the project is registered in ~/.claude-mem/cursor-projects.json. This allows the worker to automatically update your context file whenever a new summary is generated - even if it happens from Claude Code or another IDE working on the same project.

To see registered projects:

cat ~/.claude-mem/cursor-projects.json

Comparison with Claude Code

Feature	Claude Code	Cursor
Context injection	✅ additionalContext in hook output	✅ Auto-updated rules file
Injection timing	Immediate (same prompt)	Before prompt + after summary + after session
Persistence	Session only	File-based (persists across restarts)
Initial setup	Automatic	claude-mem cursor install creates initial context
MCP tool access	✅ Full support	✅ Full support
Web viewer	✅ Available	✅ Available

First Session Behavior

When you run claude-mem cursor install:

• If worker is running with existing memory → initial context is generated
• If no existing memory → placeholder file created

Context is then automatically refreshed:

• Before each prompt (ensures latest observations are included)
• After each session ends (captures new observations from the session)

Additional Access Methods

1. MCP Tools

Configure claude-mem's MCP server in Cursor for search tools:

• search(query, project, limit)
• timeline(anchor, depth_before, depth_after)
• get_observations(ids)

2. Web Viewer

Access context manually at http://localhost:37777

3. Manual Request

Ask the agent: "Check claude-mem for any previous work on authentication"

File Location

The context file is created at:

<workspace>/.cursor/rules/claude-mem-context.mdc

This is version-controlled by default. Add to .gitignore if you don't want to commit it:

.cursor/rules/claude-mem-context.mdc