SHARED UTILITIES KNOWLEDGE BASE
OVERVIEW
55 cross-cutting utilities: path resolution, token truncation, config parsing, model resolution.
STRUCTURE
shared/
├── tmux/ # Tmux TUI integration (types, utils, constants)
├── logger.ts # File-based logging (/tmp/oh-my-opencode.log)
├── dynamic-truncator.ts # Token-aware context window management (194 lines)
├── model-resolver.ts # 3-step resolution (Override → Fallback → Default)
├── model-requirements.ts # Agent/category model fallback chains (132 lines)
├── model-availability.ts # Provider model fetching & fuzzy matching (154 lines)
├── jsonc-parser.ts # JSONC parsing with comment support
├── frontmatter.ts # YAML frontmatter extraction (JSON_SCHEMA only)
├── data-path.ts # XDG-compliant storage resolution
├── opencode-config-dir.ts # ~/.config/opencode resolution (143 lines)
├── claude-config-dir.ts # ~/.claude resolution
├── migration.ts # Legacy config migration logic (231 lines)
├── opencode-version.ts # Semantic version comparison
├── permission-compat.ts # Agent tool restriction enforcement
├── system-directive.ts # Unified system message prefix & types
├── session-utils.ts # Session cursor, orchestrator detection
├── shell-env.ts # Cross-platform shell environment
├── agent-variant.ts # Agent variant from config
├── zip-extractor.ts # Binary/Resource ZIP extraction
├── deep-merge.ts # Recursive object merging (proto-pollution safe, MAX_DEPTH=50)
├── case-insensitive.ts # Case-insensitive object lookups
├── session-cursor.ts # Session message cursor tracking
├── command-executor.ts # Shell command execution (225 lines)
└── index.ts # Barrel export for all utilities
MOST IMPORTED
| Utility | Users | Purpose |
|---|---|---|
| logger.ts | 16+ | Background task visibility |
| system-directive.ts | 8+ | Message filtering |
| opencode-config-dir.ts | 8+ | Path resolution |
| permission-compat.ts | 6+ | Tool restrictions |
WHEN TO USE
| Task | Utility |
|---|---|
| Path Resolution | getOpenCodeConfigDir(), getDataPath() |
| Token Truncation | dynamicTruncate(ctx, sessionId, output) |
| Config Parsing | readJsoncFile<T>(path), parseJsonc(text) |
| Model Resolution | resolveModelWithFallback(client, reqs, override) |
| Version Gating | isOpenCodeVersionAtLeast(version) |
| YAML Metadata | parseFrontmatter(content) |
| Tool Security | createAgentToolAllowlist(tools) |
| System Messages | createSystemDirective(type), isSystemDirective(msg) |
| Deep Merge | deepMerge(target, source) |
KEY PATTERNS
3-Step Resolution (Override → Fallback → Default):
const model = resolveModelWithFallback({
userModel: config.agents.sisyphus.model,
fallbackChain: AGENT_MODEL_REQUIREMENTS.sisyphus.fallbackChain,
availableModels: fetchedModels,
})
System Directive Filtering:
if (isSystemDirective(message)) return // Skip system-generated
const directive = createSystemDirective("TODO CONTINUATION")
ANTI-PATTERNS
- Raw JSON.parse: Use
jsonc-parser.tsfor comment support - Hardcoded Paths: Use
*-config-dir.tsordata-path.ts - console.log: Use
logger.tsfor background task visibility - Unbounded Output: Use
dynamic-truncator.tsto prevent overflow - Manual Version Check: Use
opencode-version.tsfor semver safety