Natural language
Synthetic (default)
Real-world sources
CLI commands
Real-world sources
Real sources cap at 500 rows. When
--source is set, Arka never falls back to synthetic or LLM data — fetch errors are reported clearly.
World Bank indicators
gdp, gdp_per_capita, population, life_expectancy, co2, unemployment, internet
Country codes use ISO-3166 alpha-2 (e.g. IN, US). Natural language country names (India, United States) are parsed automatically.
Supported formats
csv, json, jsonl, tsv, yaml, xml, sql, markdown, xlsx
XLSX output requires openpyxl (pip install openpyxl). For richer fake values, install the optional Faker extra:
Presets
Built-in presets infer columns automatically (synthetic mode only):
Field names are matched to generators (names, emails, phones, addresses, dates, numbers, UUIDs, booleans). Use
--llm for complex custom schemas when an LLM API key is configured.
Output
Print to stdout by default, or save with-o output.csv or by passing a filename as the first argument.