effect-analyzer supports over 25 output formats. Use --format <name> on the CLI, or let auto mode select the best combination for your program.
| Format | CLI Flag | Description | Best For |
|---|
| Standard flowchart | --format mermaid | Full control-flow graph with all paths | Complex programs with branching |
| Railway | --format mermaid-railway | Linear happy path with error branches | Sequential generators |
| Execution paths | --format mermaid-paths | Each execution path as a separate flow | Understanding all possible routes |
| Enhanced | --format mermaid-enhanced | Rich annotations (types, services, errors) per node | Documentation and review |
| Service map | --format mermaid-services | Service dependency graph | Understanding DI topology |
| Error flow | --format mermaid-errors | Error producers, handlers, propagation | Debugging error handling |
| Decision tree | --format mermaid-decisions | Conditional branching visualization | Programs with many if/match |
| Cause hierarchy | --format mermaid-causes | Cause and Exit wrapping structure | Cause/Exit pattern analysis |
| Concurrency | --format mermaid-concurrency | Parallel and race fork/join structure | Programs with Effect.all/Effect.race |
| Timeline | --format mermaid-timeline | Step sequence as a timeline | Temporal ordering of steps |
| Layer graph | --format mermaid-layers | Layer composition and dependencies | Layer architecture review |
| Retry strategy | --format mermaid-retry | Retry and timeout policy visualization | Programs with retry/timeout |
| Testability | --format mermaid-testability | What needs mocking and what to test | Test planning |
| Data flow | --format mermaid-dataflow | Data dependencies between pipe steps | Understanding value flow |
| Composition | (library API) | Cross-program call graph | Multi-program projects |
| Format | CLI Flag | Description | Best For |
|---|
| JSON | --format json | Full IR serialized as JSON | Tooling integration |
| Stats | --format stats | Complexity metrics and analysis statistics | Quick complexity check |
| Explain | --format explain | Plain-English narrative of program behavior | Documentation, onboarding |
| Summary | --format summary | One-line description per program | Directory overviews |
| Matrix | --format matrix | Program-by-service dependency table | Cross-cutting dependency view |
| Showcase | --format showcase | Detailed step-by-step breakdown | Comprehensive documentation |
| Migration | --format migration | Patterns that could migrate to Effect | Adoption planning |
| Format | CLI Flag | Description | Best For |
|---|
| API docs | --format api-docs | HttpApi structure as markdown | API documentation |
| OpenAPI paths | --format openapi-paths | Minimal OpenAPI paths for spec merging | OpenAPI integration |
| OpenAPI runtime | --format openapi-runtime | Full OpenAPI spec via OpenApi.fromApi | Complete spec generation |
| Format | How to Use | Description | Best For |
|---|
| Interactive HTML | renderInteractiveHTML(ir) (library API) | Self-contained HTML with search, filtering, path explorer, themes | Exploration, sharing |
When no --format is specified, the analyzer runs in auto mode:
- Selects a baseline diagram - railway for simple programs, flowchart for complex ones
- Scores the program’s characteristics (error density, service count, concurrency, etc.)
- Adds up to 2 specialized views based on the highest-scoring characteristics
npx effect-analyze ./src/program.ts
# Equivalent to explicitly requesting auto
npx effect-analyze ./src/program.ts --format auto
All formats support the following output options:
npx effect-analyze ./src/program.ts --format mermaid-railway -o diagram.md
# Compact JSON (no indentation)
npx effect-analyze ./src/program.ts --format json --compact
npx effect-analyze ./src/program.ts --format mermaid --direction LR
# Include trivial programs (schemas, thin wrappers)
npx effect-analyze ./src/program.ts --include-trivial
