| name | codex-context-engine |
| description | Generate and load multi-layer project context documentation to reduce AI hallucination. Use before any task on a project with 50+ files, or on explicit $codex-genome command. |
| load_priority | always |
TL;DR
Generate .codex/context/genome.md for macro project understanding. Load genome.md automatically if it exists. For large projects, also generate per-module maps. This reduces hallucination by giving AI compressed project knowledge instead of raw file scanning.
Context Engine (Project Genome)
Activation
- Auto-load: If
.codex/context/genome.md exists in the project, load it at session start.
- Auto-suggest: If project has 50+ files and no
genome.md exists, suggest generating one.
- Explicit: On
$codex-genome, $generate-genome, or $genome command.
Quick Commands
$codex-genome / $genome - Generate or refresh project genome$codex-genome --force / $genome --force - Force regeneration
When to Generate
| Project Size | Action |
|---|
| < 50 files | Optional. Suggest only if user asks |
| 50-500 files | Suggest on first encounter. Shallow depth (genome.md only) |
| 500+ files | Strongly recommend. Full depth (genome.md + module maps) |
When to Load
- genome.md: Load at session start if it exists. This is your project briefing - read it before any code edit.
- Module maps: Load only the module(s) relevant to the current task. Never load all module maps at once.
How to Use Context
After loading genome.md:
- You now know the tech stack, directory structure, entry points, data models, API surface, and coding conventions.
- When working on a specific module, check if
.codex/context/modules/{module-name}.md exists and load it.
- Use this knowledge to avoid:
- Guessing import paths (genome tells you the structure)
- Wrong naming conventions (genome tells you the patterns)
- Missing dependencies (genome tells you module boundaries)
- Hallucinating APIs (genome tells you the real routes)
Script Invocation
- Use
generate_genome.py from codex-project-memory.
- Xem
skills/.system/REGISTRY.md để biết đường dẫn đầy đủ.
Script Invocation Discipline
- Always run
--help before invoking.
- Treat script as a black-box tool and execute by contract first.
- Read script source only when customization or bug fixing is required.
Freshness Check
genome.md includes a "Generated:" timestamp and file counts.- If current file count differs significantly (>20%) from
genome.md counts, suggest re-generation.
- When user restructures the project (adds/removes modules), remind to regenerate.
Output Files
| File | Purpose | Size Target |
|---|
.codex/context/genome.md | Macro project context | 500-800 words |
.codex/context/modules/{name}.md | Per-module detail | 200-400 words each |
Context Loading Budget
genome.md: always (~2000-2400 tokens)- Module maps: max 3 at a time (~600-1200 tokens each)
- Total context overhead: <5000 tokens (<4% of context window)
