| name | auto-learning |
| description | Instinct-based learning system that observes sessions via hooks and evolves patterns into skills/commands/agents. Use when the user asks about learned instincts, wants to analyze session patterns, sets up auto-learning or observation hooks, or runs $idev:instinct-status, $idev:instinct-export, $idev:instinct-import, or $idev:evolve. |
Auto-Learning - Instinct-Based Architecture
A learning system that turns Codex sessions into reusable knowledge through atomic "instincts" - small learned behaviors with confidence scoring.
The Instinct Model
An instinct is a small learned behavior:
---
id: prefer-functional-style
trigger: "when writing new functions"
confidence: 0.7
domain: "code-style"
source: "session-observation"
---
Use functional patterns over classes when appropriate.
- Observed 5 instances of functional pattern preference
- User corrected class-based approach to functional on 2025-01-15
Properties:
- Atomic — one trigger, one action
- Confidence-weighted — 0.3 = tentative, 0.9 = near certain
- Domain-tagged — code-style, testing, git, debugging, workflow, etc.
- Evidence-backed — tracks what observations created it
How It Works
Session Activity
│
│ PreToolUse/PostToolUse hooks (observe.sh → observe.py)
▼
┌─────────────────────────────────────────┐
│ observations.jsonl │
│ (tool calls + outcomes, redacted) │
└─────────────────────────────────────────┘
│
│ Observer loop (start-observer.sh, headless Haiku)
▼
┌─────────────────────────────────────────┐
│ instincts/personal/ │
│ atomic instincts with confidence │
└─────────────────────────────────────────┘
│
│ $idev:evolve clusters
▼
┌─────────────────────────────────────────┐
│ evolved/ │
│ skills / commands / agents │
└─────────────────────────────────────────┘
Quick Start
1. Enable Observation (opt-in)
The observation hooks are pre-registered by the plugin's hooks/hooks.json (PreToolUse/PostToolUse, all tools) but off by default — observe.sh exits instantly unless the global opt-in flag ~/.codex/homunculus/enabled exists. Enable with:
$idev:hooks enable observer
Disable with $idev:hooks disable observer. No settings.json editing, takes effect immediately, and the toggle is global (observations span all projects).
observe.sh is a thin wrapper that pipes the hook JSON to observe.py (the canonical implementation). The pre/post argument tells it the hook phase; if omitted, it falls back to the hook_event_name field in the payload. The hook truncates inputs/outputs at 5000 chars, redacts secret-looking values, honors capture_tools/ignore_tools from config.json, and rotates observations.jsonl into observations.archive/ past max_file_size_mb.
2. Initialize Directory Structure
mkdir -p ~/.codex/homunculus/{instincts/{personal,inherited},evolved/{agents,skills,commands}}
touch ~/.codex/homunculus/observations.jsonl
3. Run the Observer Agent (Optional)
The observer runs in the background, analyzing observations every 5 minutes (and on SIGUSR1 from the hook). It only archives observations after a successful analysis that produced an instinct:
"${PLUGIN_ROOT}/skills/auto-learning/agents/start-observer.sh"
"${PLUGIN_ROOT}/skills/auto-learning/agents/start-observer.sh" status
"${PLUGIN_ROOT}/skills/auto-learning/agents/start-observer.sh" stop
CLI and Commands
scripts/instinct-cli.py manages the instinct store. Four plugin commands wrap it:
| Command | CLI invocation | Description |
|---|
$idev:instinct-status | instinct-cli.py status | Show all instincts with confidence, by domain |
$idev:instinct-export | instinct-cli.py export [--domain] [--min-confidence] [--output] | Export sanitized instincts for sharing |
$idev:instinct-import | instinct-cli.py import <file-or-url> [--dry-run] [--force] [--min-confidence] | Import instincts; updates existing ids in place |
$idev:evolve | instinct-cli.py evolve [--generate] | Print instinct clusters; Claude writes the evolved files |
Run it directly with:
python3 "${PLUGIN_ROOT}/skills/auto-learning/scripts/instinct-cli.py" status
Configuration
config.json (in this skill's directory) is the source of truth:
{
"version": "2.0",
"observation": {
"enabled": true,
"store_path": "~/.codex/homunculus/observations.jsonl",
"max_file_size_mb": 10,
"archive_after_days": 7,
"capture_tools": ["Edit", "Write", "Bash", "Read", "Grep", "Glob"],
"ignore_tools": ["TodoWrite"]
},
"instincts": {
"personal_path": "~/.codex/homunculus/instincts/personal/",
"inherited_path": "~/.codex/homunculus/instincts/inherited/",
"min_confidence": 0.3,
"auto_approve_threshold": 0.7,
"confidence_decay_rate": 0.02,
"max_instincts": 100
},
"observer": {
"enabled": false,
"model": "haiku",
"run_interval_minutes": 5,
"min_observations_to_analyze": 20,
"patterns_to_detect": [
"user_corrections",
"error_resolutions",
"repeated_workflows",
"tool_preferences",
"file_patterns"
]
},
"evolution": {
"cluster_threshold": 3,
"evolved_path": "~/.codex/homunculus/evolved/",
"auto_evolve": false
}
}
Field reference:
observation.enabled — master switch for the observation hook (false disables capture)
observation.capture_tools — if non-empty, ONLY these tools are observed
observation.ignore_tools — tools never observed (checked before capture_tools)
observation.max_file_size_mb — observations.jsonl rotates to the archive past this size
observation.archive_after_days — retention hint for archived observations
instincts.min_confidence — floor for keeping an instinct
instincts.auto_approve_threshold — confidence at which an instinct applies without asking
instincts.confidence_decay_rate — weekly decay when a pattern stops being observed
instincts.max_instincts — cap on the instinct store; prune lowest-confidence first
observer.enabled — whether the background observer should run
observer.min_observations_to_analyze — observations required before an analysis run (read by start-observer.sh)
evolution.cluster_threshold — instincts required to form an evolution cluster
evolution.auto_evolve — if true, evolution may be proposed without an explicit $idev:evolve
You can also disable capture entirely by creating ~/.codex/homunculus/disabled.
File Structure
~/.codex/homunculus/
├── observations.jsonl # Current session observations
├── observations.archive/ # Rotated + processed observations
├── observer.log # Background observer log
├── instincts/
│ ├── personal/ # Auto-learned instincts
│ └── inherited/ # Imported from others
└── evolved/
├── agents/ # Evolved specialist agents
├── skills/ # Evolved skills
└── commands/ # Evolved commands
Confidence Scoring
| Score | Meaning | Behavior |
|---|
| 0.3 | Tentative | Suggested but not enforced |
| 0.5 | Moderate | Applied when relevant |
| 0.7 | Strong | Auto-approved for application |
| 0.9 | Near-certain | Core behavior |
Confidence increases when a pattern is repeatedly observed, the user doesn't correct the behavior, or similar instincts from other sources agree.
Confidence decreases when the user explicitly corrects the behavior, the pattern isn't observed for extended periods (see confidence_decay_rate), or contradicting evidence appears.
Privacy
- Observations stay local on your machine
- The hook redacts secret-looking values (api keys, tokens, passwords) before writing
- Export sanitizes absolute file paths and secrets; only instinct patterns are shared
- You control what gets exported
Architecture inspired by the Homunculus continuous-learning project.