JSON profile

Each tabalyst report run writes a JSON profile next to the HTML report, with the same name: orders.html comes with orders.json. The profile holds the complete analysis result; the HTML report is rendered from it. Use it to read Tabalyst results from scripts or other tools.

The format is experimental: it can change incompatibly between releases. Always check format_version and format_revision first. This page describes format 0.1.0a, revision 2.

Example

A shortened profile for a five-row orders.csv:

{
  "format_version": "0.1.0a",
  "format_revision": 2,
  "generated_at": "2026-09-25T22:25:07.873024Z",
  "processing_seconds": 0.0098,
  "source": {
    "filename": "orders.csv",
    "size_bytes": 274,
    "sha256": "7d426449e1217d4dbcad1e7e4c862d360c63d927cb775caa48007d70ac36c0c8",
    "encoding": "utf-8-sig",
    "delimiter": ","
  },
  "config": { "...": "effective configuration" },
  "summary": {
    "row_count": 5,
    "column_count": 6,
    "missing_count": 2,
    "duplicate_row_count": 1,
    "with_issues_column_count": 2
  },
  "date_summary": { "...": "present when a column contains dates" },
  "columns": [
    {
      "id": "column_3",
      "name": "amount",
      "position": 3,
      "inferred_type": "mixed",
      "type_counts": { "number": 3, "text": 1 },
      "type_confidence": 0.75,
      "missing_count": 1,
      "missing_percent": 20.0,
      "with_issues": true,
      "distinct_count": 3,
      "examples": ["25.00", "12.50", "not available"],
      "semantic_type": null
    }
  ],
  "issues": [
    {
      "code": "duplicate_rows",
      "severity": "warning",
      "message": "Duplicate rows beyond their first occurrence",
      "count": 1,
      "column_ids": [],
      "row_numbers": [4]
    }
  ],
  "preview": [
    {
      "row_number": 1,
      "values": ["001", "Alice", "12.50", "2026-01-01", "true", "First order"]
    }
  ]
}

Top-level fields

Field	Type	Content
format_version	string	Format family, "0.1.0a" during the alpha
format_revision	integer	Revision within the family, increased for each structural or semantic change
generated_at	string	UTC date and time of the analysis (ISO 8601)
processing_seconds	number	CSV reading and analysis time, in seconds
source	object	The analyzed file (see below)
config	object	The effective configuration, after merging defaults, the configuration file and command options. Same structure as the configuration file
summary	object	Dataset-level counts (see below)
date_summary	object or null	Dataset-level date counts, when at least one column contains date values
columns	array	One profile per column, in file order
issues	array	Detected problems (see below)
preview	array	The first rows, with raw values

source

Field	Content
filename	File name, without folder
size_bytes	File size in bytes
sha256	SHA-256 hash of the file, to check that two profiles describe the same file
encoding	Text encoding used to read the file
delimiter	Field delimiter used to read the file

summary

Counts over the whole dataset:

• size: row_count, column_count, cell_count;
• missing values: missing_count, missing_percent;
• normalization: trim_count, collapse_internal_whitespace_count;
• structure: duplicate_row_count, empty_row_count, empty_column_count, constant_column_count, with_issues_column_count;
• column families: numeric_column_count, date_column_count, string_column_count;
• type distributions: inferred_type_counts, inferred_type_percents, semantic_type_counts, semantic_type_percents.

Percentages are numbers from 0 to 100.

columns

Each column profile always contains:

Field	Content
id	Stable identifier from the position, such as column_3. Use it rather than name, which can be blank or repeated
name	Header text
position	Position in the file, starting at 1
inferred_type	empty, boolean, integer, number, date, text or mixed
type_counts	Number of present values of each type
type_confidence	Share of present values accepted by the inferred type, from 0 to 1. For mixed columns, the share of the largest type family
type_error_count, type_error_percent	Values outside the inferred type; null for mixed columns
missing_count, missing_percent	Missing cells
with_issues	true when the column has missing values or its type is mixed
normalization	Cells changed by whitespace trimming and collapsing
distinct_count	Number of distinct values after normalization
examples	A few representative values
value_profile	Value occurrences, complete or sampled (see selection)
semantic_type	enum, date or null

Depending on the column, these objects are also present (otherwise null):

Field	Present for	Content
numeric	integer and number columns with finite values	minimum, maximum, range, mean, median
date_profile	Columns containing date values, even when their type is mixed	Valid, ambiguous and invalid counts, detected formats and their breakdown
string_profile	text columns	Length statistics, length distribution and representative examples
enum	Enumeration candidates	Observed distinct values, coverage and confidence

issues

Each issue has a code, a severity (warning or info), an English message, a count, the affected column_ids and up to 10 row_numbers. Row numbers count data records from 1; the header is not counted.

code	Severity	Meaning
duplicate_rows	warning	Rows repeating an earlier row, beyond its first occurrence
missing_values	warning	Missing cells
empty_columns	warning	Columns without any present value
mixed_types	warning	Columns with mixed value types
ambiguous_headers	warning	Blank or repeated column names
constant_columns	info	Columns with a single distinct present value
trimmed_cells	info	Cells changed by trimming surrounding whitespace
collapsed_whitespace	info	Cells changed by collapsing repeated internal whitespace

An issue is listed only when its count is above zero, except trimmed_cells and collapsed_whitespace, which are always listed.

preview

The first rows of the file (10 by default, set by preview_rows in the configuration), each with its row_number and raw values in column order. The preview size does not affect the analysis, which always reads every row.

Versioning

• format_version names the experimental format family. It stays "0.1.0a" during the alpha.
• format_revision increases for each structural or semantic change. It does not change for report styling or performance improvements.
• Revisions can be incompatible, and no migration is provided. See the profile format changelog.

The profile contains values from the source file, in examples, value_profile and preview. Share it as you would share the data.