Second Brain
A personal knowledge base for building understanding that compounds over time. Not a note dump - a structured system for capturing knowledge you can actually retrieve and use.
Philosophy
Your second brain should:
- Capture understanding, not just facts - Write for your future self who forgot the context
- Be retrievable - Structured so you can find things when you need them
- Stay evergreen - No private details, credentials, or time-sensitive data
- Reflect real experience - Only save what you've actually learned or used
Before saving: Will future-me thank me for this?
Namespace Structure
public/ --> Shareable knowledge
concepts/ --> How things work
[domain]/ --> Organize by topic
[concept-name] --> Individual concepts
toolbox/ --> Tools and technologies
_index --> Master index of tools
[category]/ --> Group by type
[tool-name] --> Individual tools
patterns/ --> Reusable solutions
[domain]/ --> Design patterns, workflows
references/ --> Quick-reference material
[topic]/ --> Cheatsheets, syntax, APIs
private/ --> Personal only
notes/ --> Scratchpad, drafts
journal/ --> Dated reflections
Example domains: programming, devops, design, business, data, security, productivity
Content Formats
Concepts
For understanding how something works:
CONCEPT NAME
============
What it is:
[One-line definition]
Why it matters:
[What problem it solves, when you'd need it]
How it works:
[Explanation with examples]
[ASCII diagrams for architecture/flows where helpful]
+----------+ +----------+
| Client | ---> | Server |
+----------+ +----------+
Key insight:
[The "aha" moment - what makes this click]
Related: [links to related concepts]
Toolbox Entries
For tools and technologies you've actually used:
TOOL NAME
Category: [category]
Website: [url]
Cost: [free/paid/freemium]
What it does:
[Brief description]
Why I use it:
[Personal experience - what problem it solved for you]
When to reach for it:
[Scenarios where this is the right choice]
Quick start:
[Minimal setup/usage to get going]
Gotchas:
[Things that tripped you up]
Patterns
For reusable solutions:
PATTERN NAME
Problem:
[What situation triggers this pattern]
Solution:
[The approach, with code/pseudocode if relevant]
Trade-offs:
[Pros and cons, when NOT to use it]
Example:
[Concrete implementation]
References
For quick-lookup material:
REFERENCE: [TOPIC]
[Organized, scannable content]
[Tables, lists, code snippets]
[Minimal prose, maximum signal]
Interaction Rules
Saving Knowledge
Always confirm before saving:
- "Want me to save this to your second brain?"
- Show draft of what will be saved
- Save after confirmation
- Confirm what was saved and where
Retrieving Knowledge
When relevant topics come up:
- Search for existing knowledge
- Surface related concepts
- Connect new learning to existing understanding
Maintaining Quality
Before saving, verify:
- Written for future self who forgot context
- Includes the WHY, not just the WHAT
- Has concrete examples
- No credentials, API keys, or private paths
- Structured for retrieval
Anti-Patterns
- Don't auto-save - Always ask first
- Don't save unused tools - Only tools actually used
- Don't save half-understood concepts - Learn first, save after
- Don't include secrets - No API keys, passwords, tokens
- Don't create shallow entries - If you can't explain it well, don't save it
- Don't duplicate - Check if it exists first, update if needed
API Usage
Use the wrapper script:
{baseDir}/scripts/ensue-api.sh <method> '<json_args>'
Operations
Search knowledge:
{baseDir}/scripts/ensue-api.sh discover_memories '{"query": "how does X work", "limit": 5}'
List by namespace:
{baseDir}/scripts/ensue-api.sh list_keys '{"prefix": "public/concepts/", "limit": 20}'
Get specific entries:
{baseDir}/scripts/ensue-api.sh get_memory '{"key_names": ["public/concepts/programming/recursion"]}'
Create entry:
{baseDir}/scripts/ensue-api.sh create_memory '{"items":[
{"key_name":"public/concepts/domain/name","description":"Short description","value":"Full content","embed":true}
]}'
Update entry:
{baseDir}/scripts/ensue-api.sh update_memory '{"key_name": "public/toolbox/_index", "value": "Updated content"}'
Delete entry:
{baseDir}/scripts/ensue-api.sh delete_memory '{"key_name": "public/notes/old-draft"}'
Toolbox Index
Maintain public/toolbox/_index as master reference:
TOOLBOX INDEX
=============
Categories:
languages/ Programming languages
frameworks/ Libraries and frameworks
devtools/ Development utilities
infrastructure/ Deployment, hosting, CI/CD
productivity/ Workflow and productivity tools
data/ Databases, analytics, data tools
Recent additions:
[tool] - [one-line description]
Browse: "show my toolbox" or "what tools do I have for [category]"
Intent Mapping
| User says | Action |
|---|
| "save this", "remember this" | Draft entry, confirm, save |
| "what do I know about X" | Search and retrieve relevant entries |
| "add [tool] to toolbox" | Create toolbox entry |
| "list my [domain] concepts" | list_keys for that namespace |
| "show my toolbox" | Show toolbox index |
| "update [entry]" | Fetch, show diff, update |
| "delete [entry]" | Confirm, delete |
| "search for [topic]" | Semantic search across all knowledge |
Setup
Requires ENSUE_API_KEY environment variable.
Get your key at: https://www.ensue-network.ai/dashboard
Configure in clawdbot.json:
"skills": {
"entries": {
"second-brain": {
"apiKey": "your-ensue-api-key"
}
}
}
Security
- NEVER log or display the API key
- NEVER store credentials, tokens, or secrets in entries
- NEVER include personal file paths or system details
