Generate Synthetic Dataset
data.generate_synthetic_dataset
Overview
You declare the columns you want and a seed string; we return that many rows of invented values. Twelve generators cover integers, decimals, booleans, strings, categories, dates, date-times and UUID-shaped identifiers, and each cell is derived independently from the digest of your seed, the column name, the row index and the generator — so the same request always returns the same table, and adding a column or raising the row count leaves every cell you already had byte-identical. There is no embedded corpus of real names, addresses or companies here, no value carries a valid checksum, and every email domain must be one of the reserved names that cannot reach a real mailbox. Bounds for dates come from you, because this skill reads no clock.
Test data that looks real should not be real, and a fixture nobody can regenerate is a file somebody has to keep.
Reliability
Within version 1.0.0 the same schema, count and seed give a byte-identical table on any machine, under any locale, time zone or default charset. Across versions that is not promised, which is why the descriptor declares determinism as version-sensitive and _meta.generatorProfile echoes synthetic-1: a caller needing a frozen corpus stores the table, not the seed. The stream is SplitMix64 and each cell is seeded independently from the SHA-256 digest of the seed, the column name, the row index and the generator, so appending a column or raising count leaves every earlier cell unchanged instead of reshuffling everything after the insertion point. Nothing reads platform randomness and nothing reads a clock. Two generators need saying out loud: UUID_V4_FROM_SEED sets the version and variant nibbles so the value is shaped like a v4 UUID, but its bits come from the seed, so it is reproducible and therefore predictable and must never be a token, a nonce or a security identifier; SYNTHETIC_EMAIL accepts only domains ending in .invalid, .example, .test or .localhost, the names RFC 2606 and RFC 6761 reserve. Any generated value may coincide with a real one by accident, so none of them is safe for an identity-bearing production field. Fourteen refusals, none retryable unchanged: SYNTHETIC_SCHEMA_INVALID, SYNTHETIC_COLUMN_LIMIT_EXCEEDED above 64 columns and SYNTHETIC_COLUMN_NAME_DUPLICATE when two columns share a name, so rename one column before retrying; SYNTHETIC_TYPE_UNSUPPORTED, SYNTHETIC_GENERATOR_UNSUPPORTED and SYNTHETIC_GENERATOR_TYPE_MISMATCH when a column names something outside the closed vocabularies or pairs a generator with the wrong type; SYNTHETIC_PARAMS_INVALID and SYNTHETIC_RANGE_INVALID for a parameter that is missing, mistyped or cannot produce a value; SYNTHETIC_DOMAIN_NOT_RESERVED for an email domain that could reach a real mailbox; SYNTHETIC_COUNT_INVALID outside 1 to 100000 and SYNTHETIC_SEED_INVALID outside 1 to 128 code points; SYNTHETIC_OUTPUT_MODE_UNSUPPORTED for an output outside TABLE and ROWS; SYNTHETIC_WORK_REFUSED above 2000000 projected cells; and SYNTHETIC_OUTPUT_TOO_LARGE above 1048576 projected bytes, which is half the inline ceiling and is checked from the declared column widths before a single cell exists. No time limit is declared because generation is linear in cells with no data-dependent branch, so bytes are the binding resource and a wall clock would be a weaker way of saying the same thing.
Context footprint
Returns the generated table, so the response is as large as the request asks for, up to the 1048576-byte projected ceiling. A successful call costs 2 execution credits.
When to use it
When you need a table of the right shape and none of the right content, and you want the same table again tomorrow from the same seed.
When you already hold the records and need them pseudonymised, or when the value has to be unpredictable.
Scope
Non-goals
- Does not embed any corpus of real names, addresses, companies or identifiers
- Does not produce a checksum-valid IBAN, VAT number, card number or national identifier
- Does not pseudonymise records you already hold — data.anonymize_dataset does that
- Does not guarantee any generated value is unique or unused in the real world
- Does not read a clock, so every date range is a caller input
Properties
Capabilities
Cost & billing
Flat rate per invocation
File handling
How we handle your data
What this means
This skill may receive sensitive content and may return submitted, transformed, extracted, or reformatted content.
Squillify guarantees
- Runs inside Squillify
- This skill runs inside Squillify.
- Payloads are not sent to an external service by this skill.
- Squillify does not permanently store submitted payloads.
- Telemetry records metadata only, not submitted content.
- Submitted payloads are not used for training.
- Submitted payloads are not reviewed by humans.
- This skill does not target sensitive data.
- The response may contain submitted or transformed content.
Your responsibility
Squillify does not determine whether submitted content is sensitive. Your application is responsible for deciding what data it is allowed to submit. Your application is responsible for securing the response.
Input schema
| Field | Type | Required | Description |
|---|---|---|---|
| schema | object | Yes | Closed synthetic schema of uniquely named columns, each declaring name, type, generator and optional params. |
| count | integer | Yes | How many rows to generate. |
| seed | string | Yes | Seed string that makes the table reproducible within this version. |
| output | string | No | Return shape; omit it for TABLE. |
Output schema
| Field | Type | Required | Description |
|---|---|---|---|
| table | object | Yes | Generated table as positional arrays under TABLE or row objects under ROWS. |
| warnings | array | Yes | Bounded array of 0 through 64 closed generator warnings, each a stable code and a safe message. |
| summary | object | Yes | Closed generated-table size receipt with rowCount, columnCount, cells and UTF-8 bytes. |
| work | object | Yes | Closed admission decision in generated cells with projected size and the budget ceiling. |
| _meta | object | Yes | Closed provenance naming the generator profile and echoed seed. |
API contract
POST /v1/executecurl -sS -X POST "$BASE/v1/execute" -H "Authorization: Bearer $KEY" -H 'Content-Type: application/json' -d '{"skillKey":"data.generate_synthetic_dataset","input":{"schema":{"columns":[{"name":"id","type":"INTEGER","generator":"SEQUENTIAL_INTEGER","params":{"start":1,"step":1}}]},"count":2,"seed":"fixture-a"}}'import { Squillify } from "@squillify/sdk";
const sq = new Squillify({ apiKey: process.env.SQUILLIFY_API_KEY });
const { output } = await sq.execute("data.generate_synthetic_dataset", {"schema":{"columns":[{"generator":"SEQUENTIAL_INTEGER","params":{"start":1,"step":1},"type":"INTEGER","name":"id"},{"generator":"CATEGORICAL","params":{"values":["free","pro"]},"type":"ENUM","name":"tier"}]},"seed":"fixture-a","count":2});Errors
| Code | HTTP | Retryable | Description |
|---|---|---|---|
| VALIDATION_ERROR | 400 | No | The request payload failed schema validation. |
| UNAUTHORIZED | 401 | No | Missing or invalid API key. |
| SKILL_NOT_ACCESSIBLE | 403 | No | The API key is not granted access to this skill. |
| SKILL_NOT_AVAILABLE_FOR_PLAN | 403 | No | This skill is not included in your current plan. |
| PLAN_ELIGIBILITY_UNAVAILABLE | 503 | Yes | Plan eligibility could not be decided. Retry after backoff. |
| SKILL_NOT_FOUND | 404 | No | The requested skill or version does not exist. |
| TENANT_RATE_LIMITED | 429 | Yes | Request rate limit exceeded. Retry after backoff. |
| QUOTA_EXCEEDED | 429 | Yes | Plan quota exhausted. Retryable once the quota period resets. |
| EXECUTION_TIMEOUT | 504 | Yes | Execution exceeded the allowed time budget. |
| SYNTHETIC_SCHEMA_INVALID | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_COLUMN_LIMIT_EXCEEDED | 429 | No | A size, quota, rate, or time limit was exceeded. |
| SYNTHETIC_COLUMN_NAME_DUPLICATE | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_TYPE_UNSUPPORTED | 400 | No | The skill does not support the requested variant. |
| SYNTHETIC_GENERATOR_UNSUPPORTED | 400 | No | The skill does not support the requested variant. |
| SYNTHETIC_GENERATOR_TYPE_MISMATCH | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_PARAMS_INVALID | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_RANGE_INVALID | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_DOMAIN_NOT_RESERVED | 403 | No | The operation is forbidden by policy or permissions. |
| SYNTHETIC_COUNT_INVALID | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_SEED_INVALID | 400 | No | The request payload failed this skill's input validation. |
| SYNTHETIC_OUTPUT_MODE_UNSUPPORTED | 400 | No | The skill does not support the requested variant. |
| SYNTHETIC_WORK_REFUSED | 429 | No | A size, quota, rate, or time limit was exceeded. |
| SYNTHETIC_OUTPUT_TOO_LARGE | 429 | No | A size, quota, rate, or time limit was exceeded. |
Other limits
| Limit | Value |
|---|---|
| Recommended inline bytes | 32 KiB |
Limitations
- Does not embed any corpus of real names, addresses, companies or identifiers
- Does not produce a checksum-valid IBAN, VAT number, card number or national identifier
- Does not pseudonymise records you already hold — data.anonymize_dataset does that
- Does not guarantee any generated value is unique or unused in the real world
- Does not read a clock, so every date range is a caller input
- Generating tokens, nonces or any security identifier
- Producing values for an identity-bearing production field
- Anonymising a real dataset
How to call
POST /v1/execute (requires authentication)
{
"skillKey": "data.generate_synthetic_dataset",
"input": {
"schema": {
"columns": [
{
"generator": "SEQUENTIAL_INTEGER",
"params": {
"start": 1,
"step": 1
},
"type": "INTEGER",
"name": "id"
},
{
"generator": "CATEGORICAL",
"params": {
"values": [
"free",
"pro"
]
},
"type": "ENUM",
"name": "tier"
}
]
},
"seed": "fixture-a",
"count": 2
}
}Examples
Two rows of an id and a category
{
"schema": {
"columns": [
{
"generator": "SEQUENTIAL_INTEGER",
"params": {
"start": 1,
"step": 1
},
"type": "INTEGER",
"name": "id"
},
{
"generator": "CATEGORICAL",
"params": {
"values": [
"free",
"pro"
]
},
"type": "ENUM",
"name": "tier"
}
]
},
"seed": "fixture-a",
"count": 2
}{
"warnings": [],
"_meta": {
"generatorProfile": "synthetic-1",
"seedEcho": "fixture-a"
},
"table": {
"rows": [
[
1,
"free"
],
[
2,
"pro"
]
],
"columns": [
"id",
"tier"
]
},
"work": {
"projected": 4,
"budget": 2000000
},
"summary": {
"rowCount": 2,
"columnCount": 2,
"cells": 4,
"bytes": 9
}
}Row objects instead of positional arrays
{
"count": 1,
"schema": {
"columns": [
{
"generator": "SEQUENTIAL_INTEGER",
"params": {
"start": 10,
"step": 1
},
"type": "INTEGER",
"name": "id"
}
]
},
"seed": "fixture-rows",
"output": "ROWS"
}{
"warnings": [],
"_meta": {
"generatorProfile": "synthetic-1",
"seedEcho": "fixture-rows"
},
"table": {
"rows": [
{
"id": 10
}
]
},
"work": {
"projected": 1,
"budget": 2000000
},
"summary": {
"rowCount": 1,
"columnCount": 1,
"cells": 1,
"bytes": 2
}
}Recommended use cases
- Filling a test database with realistic-shaped rows
- Building a reproducible fixture for a load test
- Demonstrating a dashboard without exposing customer data
Avoid for
- Generating tokens, nonces or any security identifier
- Producing values for an identity-bearing production field
- Anonymising a real dataset
Related skills
Composable with
Safety & privacy
- Runs without calling any external service.
- Your payloads are never stored permanently.
- Telemetry captures metadata only — never your payload contents.
- We never train models on your payloads.
- No human reviews your payloads.