cortex/USAGE.md

Cortex — AI Project Memory & Knowledge Graph

Overview

Cortex is a CLI tool and web server for storing, linking, and searching project knowledge as a graph of typed nodes and edges. It supports hybrid search (BM25 + vector similarity + freshness), auto-decay of stale nodes, and a web portal for visualization.

Data is stored in .memory/cortex.db (SQLite) in the current working directory.

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CLI Reference

All commands are invoked as memory <command>.

memory add <kind>

Add a node to the knowledge graph.

Argument / Option	Required	Description
<kind>	yes	Node kind: memory, component, task, decision
-t, --title <title>	yes	Node title
-c, --content <content>	no	Node content/description
--tags <tags>	no	Comma-separated tags
--status <status>	no	Status (e.g. todo, doing, done, active, deprecated)

memory add memory -t "Auth flow design" -c "OAuth2 PKCE flow for SPA" --tags auth,security --status active
memory add task -t "Implement login page" --status todo
memory add decision -t "Use PostgreSQL" -c "Chose Postgres over MySQL for JSON support"
memory add component -t "UserService" -c "Handles user CRUD operations" --tags backend

memory query <text>

Search the knowledge graph using natural language. Uses hybrid BM25 + vector + freshness scoring.

Argument / Option	Required	Description
<text>	yes	Natural language search query
--kind <kind>	no	Filter by node kind
--limit <n>	no	Max results (default: 10)
--format <fmt>	no	Output format: text or json (default: text)

memory query "authentication"
memory query "database decisions" --kind decision
memory query "user service" --limit 5 --format json

memory show <id>

Show a node's full details and its connections. The <id> can be a full UUID or a unique prefix.

Each call to show updates the node's lastAccessedAt timestamp, which affects freshness scoring.

Argument / Option	Required	Description
<id>	yes	Node ID or unique prefix
--format <fmt>	no	Output format: text or json (default: text)

memory show abc123
memory show abc123 --format json

memory list

List nodes in the knowledge graph.

Option	Required	Description
--kind <kind>	no	Filter by kind
--status <status>	no	Filter by status
--tags <tags>	no	Comma-separated tags to filter
--limit <n>	no	Max results
--stale	no	Include stale/decayed nodes
--format <fmt>	no	Output format: text or json (default: text)

memory list
memory list --kind task --status todo
memory list --tags auth,security
memory list --stale
memory list --format json

memory update <id>

Update an existing node's fields.

Argument / Option	Required	Description
<id>	yes	Node ID or unique prefix
-t, --title <title>	no	New title
-c, --content <content>	no	New content
--status <status>	no	New status
--tags <tags>	no	Replace tags (comma-separated)
--stale	no	Mark as stale

memory update abc123 --status done
memory update abc123 -t "Updated title" -c "New content"
memory update abc123 --tags newtag1,newtag2

memory remove <id>

Remove a node. Default is soft delete (marks as stale). Use --hard for permanent deletion.

Argument / Option	Required	Description
<id>	yes	Node ID or unique prefix
--hard	no	Permanently delete instead of marking stale

memory remove abc123
memory remove abc123 --hard

memory link <fromId> <toId>

Create a directed edge between two nodes.

Argument / Option	Required	Description
<fromId>	yes	Source node ID or prefix
<toId>	yes	Target node ID or prefix
--type <type>	yes	Edge type: depends_on, contains, implements, blocked_by, subtask_of, relates_to, supersedes, about

memory link abc123 def456 --type depends_on
memory link abc123 def456 --type contains

memory graph [id]

Visualize the knowledge graph as an ASCII tree. Optionally root at a specific node.

Argument	Required	Description
[id]	no	Root node ID or prefix. Omit for full graph.

memory graph
memory graph abc123

memory decay

Run auto-decay to mark old untouched nodes as stale. Nodes whose lastAccessedAt exceeds the threshold are marked stale and hidden from default listings and search.

Option	Required	Description
--days <number>	no	Max age in days before decay (default: 180)

memory decay
memory decay --days 90
memory decay --days 0   # decay all nodes not accessed today

memory serve

Start the Cortex Portal web server. Auto-decay runs on startup and every 24 hours.

Option	Required	Description
-p, --port <number>	no	Port number (default: 3100)

memory serve
memory serve --port 8080

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Node Kinds

Kind	Purpose
memory	General knowledge, notes, context
component	Code components, services, modules
task	Work items, todos
decision	Architectural or design decisions

Edge Types

Type	Meaning
depends_on	Source depends on target
contains	Source contains target
implements	Source implements target
blocked_by	Source is blocked by target
subtask_of	Source is a subtask of target
relates_to	General relationship
supersedes	Source supersedes/replaces target
about	Source is about target

Search Scoring

Search combines three signals:

• BM25 (weight 0.25) — text relevance
• Vector similarity (weight 0.60) — semantic similarity via embeddings (requires Ollama)
• Freshness (weight 0.15) — exponential decay based on lastAccessedAt

Freshness multiplier: e^(-0.01 * ageDays) — half-life ~69 days. Recently accessed nodes are boosted; old untouched nodes are penalized but not zeroed.

REST API

The web server exposes these endpoints under /api:

Method	Path	Description
GET	/api/nodes	List nodes. Query params: kind, status, tags, limit, includeStale
GET	/api/nodes/:id	Get node + connections
POST	/api/nodes	Create node. Body: { kind, title, content?, status?, tags?, metadata? }
PATCH	/api/nodes/:id	Update node. Body: { title?, content?, status?, tags?, metadata?, isStale? }
DELETE	/api/nodes/:id	Delete node. Query param: hard=true for permanent delete
POST	/api/edges	Create edge. Body: { fromId, toId, type, metadata? }
DELETE	/api/edges/:id	Delete edge
GET	/api/graph	Get full graph (nodes + edges) for visualization
POST	/api/search	Search. Body: { text, options?: { kind?, tags?, limit?, includeStale? } }