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Usage Guide & Tech FAQ
Step-by-step help & technical notesUsage Guide
- Describe the target shape via JSON Schema, TS samples, or example JSON—specificity improves inference.
- Declare constraints (email, uuid, enums, min/max); bare `string` fields yield meaningless filler.
- Generate a tiny batch first (e.g., n=3) to verify empty arrays, nullables, and deep nesting.
- For snapshot tests, fix the RNG seed or disable randomness if available to avoid flaky CI.
- Feed outputs directly into API mocks (MSW, json-server) as response bodies.
- When synthesizing PII-like fields, use obviously fake ranges/watermarks to prevent mistaken real data.
- For load tests, chunk generation/stream writes instead of stringifying giant arrays at once.
- Guide locale/timezone fields with explicit samples rather than defaults.
- Validate exported JSON against schemas to ensure required fields/types hold.
- Tear down mock accounts after integration tests so passwords never drift into prod configs.
- Read the title and description first to confirm this utility matches your task (avoid using the wrong tool and misinterpreting output).
- Paste or type input in the editor; if a sample/template is provided, load it first to learn the expected output shape.
Related Tech Knowledge
- Generators infer from names/types (`email`, `createdAt`); ambiguous names misclassify fields.
- Random distributions ≠ real-world stats—not suitable for ML training or precise perf models.
- Faker upgrades change sample shapes—pin versions for golden tests.
- Cycles/deep recursion need schema caps to avoid stack overflows or tab crashes.
- Unique constraints may collide under randomness—increase cardinality or dedupe post-process.
- Regex-backed fields need engine support; complex patterns may degrade to arbitrary strings.
- Separate OpenAPI “documentation examples” from “test data” responsibilities.
- Security/isolation: never let mock payloads feed production telemetry—gate via env flags.
- Browser generation is single-threaded; huge counts belong in Node/CLI tools.
- Compliance: don’t seed mocks from real user rows; synthetic data still needs minimization discipline.
- Core parsing and computation run in your browser; by default your raw business payload is not persisted to this site’s servers (see on-page privacy notes).
- The pipeline is typically: read input → parse (lexical/syntactic/structured) → transform → render; failures aim to be diagnosable.