> ## Documentation Index > Fetch the complete documentation index at: https://docs.platform.toloka.ai/docs/llms.txt > Use this file to discover all available pages before exploring further. # Start a dataset export > Send field names or IDs in `fields`. Returns an export to poll for a download link. The file is a JSON array of dataset values; it does not contain pipeline run outputs. ## OpenAPI ````yaml /api-reference/openapi.json post /datasets/{datasetId}/exports openapi: 3.1.0 info: description: >- Manage projects, datasets, labeling pipelines, and model training. **Beta:** endpoints, request and response shapes, and error contracts can change without notice or a backward-compatibility promise. title: Toloka Platform API version: 2.0.0 servers: - url: https://platform.toloka.ai/api/v2-beta security: - apiKeyAuth: [] - scopedTokenAuth: [] tags: - description: The authenticated API key owner. name: Account - description: A project is the container for pipelines, datasets, and files. name: Projects - description: Rows and typed fields. Field schemas are immutable once created. name: Datasets - description: Append rows to a dataset from a file. name: Dataset uploads - description: Read a dataset out as a file. name: Dataset exports - description: A pipeline is a graph of nodes that processes each dataset item. name: Pipelines - description: The nodes, connections, fields, and version of a pipeline graph. name: Pipeline graph - description: Execute a pipeline over a dataset and inspect each item. name: Runs - description: Per-node checks that a pipeline must pass before deployment. name: Checks - description: Named credentials available to pipeline code. name: Secrets - description: Project files available to pipeline code and labeling interfaces. name: Files - description: >- Global, read-only catalog of the models a synthetic generation node can use, with their budget bounds. name: Generation models - description: >- Global, read-only catalog of the expert audience: the values a node `audience` filter can use. name: Audience - description: >- Project lists of experts a node can take its workforce from with `audienceMode: service`. Available only to teams with the audience service enabled. name: Expert lists - description: >- Experts banned in a project: they cannot be invited and are removed from the work they are in. Available only to teams with expert bans enabled. name: Expert ban list - description: Global, read-only base model catalog. name: Base models - description: Project-owned mutable model-training drafts. name: Trainings - description: Project-owned Models and immutable Model Versions. name: Models - name: Batch inference paths: /datasets/{datasetId}/exports: post: tags: - Dataset exports summary: Start a dataset export description: >- Send field names or IDs in `fields`. Returns an export to poll for a download link. The file is a JSON array of dataset values; it does not contain pipeline run outputs. operationId: createDatasetExport parameters: - in: path name: datasetId required: true schema: $ref: '#/components/schemas/DatasetId' requestBody: content: application/json: schema: description: Select dataset fields to export as a JSON array. properties: fields: description: >- Fields to include in the export, identified by field name or id. items: type: string minItems: 1 type: array format: default: json-array description: >- Emit the selected fields as one JSON array. The default when format is omitted. enum: - json-array type: string required: - fields type: object responses: '200': content: application/json: schema: $ref: '#/components/schemas/ExportJob' description: Export started headers: RateLimit-Limit: $ref: '#/components/headers/RateLimit-Limit' RateLimit-Policy: $ref: '#/components/headers/RateLimit-Policy' RateLimit-Remaining: $ref: '#/components/headers/RateLimit-Remaining' RateLimit-Reset: $ref: '#/components/headers/RateLimit-Reset' X-Request-Id: $ref: '#/components/headers/X-Request-Id' '400': description: Unknown field name or id headers: RateLimit-Limit: $ref: '#/components/headers/RateLimit-Limit' RateLimit-Policy: $ref: '#/components/headers/RateLimit-Policy' RateLimit-Remaining: $ref: '#/components/headers/RateLimit-Remaining' RateLimit-Reset: $ref: '#/components/headers/RateLimit-Reset' X-Request-Id: $ref: '#/components/headers/X-Request-Id' '404': description: Dataset not found headers: RateLimit-Limit: $ref: '#/components/headers/RateLimit-Limit' RateLimit-Policy: $ref: '#/components/headers/RateLimit-Policy' RateLimit-Remaining: $ref: '#/components/headers/RateLimit-Remaining' RateLimit-Reset: $ref: '#/components/headers/RateLimit-Reset' X-Request-Id: $ref: '#/components/headers/X-Request-Id' '429': description: Rate limit exceeded headers: RateLimit-Limit: $ref: '#/components/headers/RateLimit-Limit' RateLimit-Policy: $ref: '#/components/headers/RateLimit-Policy' RateLimit-Remaining: $ref: '#/components/headers/RateLimit-Remaining' RateLimit-Reset: $ref: '#/components/headers/RateLimit-Reset' X-Request-Id: $ref: '#/components/headers/X-Request-Id' x-codeSamples: - label: TypeScript SDK lang: typescript source: | import { createClient } from "@toloka-platform/sdk"; const client = createClient({ baseUrl: "https://platform.toloka.ai", apiKey: process.env.TOLOKA_API_KEY!, }); const exportJob = await client.datasets.startExport({ datasetId: "ds.019a0000-0000-7000-8000-000000000001", fields: [ "text" ] }); console.log(exportJob); components: schemas: DatasetId: description: Dataset ID with prefix `ds.`. pattern: >- ^ds\.[0-9a-f]{8}-[0-9a-f]{4}-[7][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$ type: string ExportJob: description: >- An asynchronous dataset export job. Failed jobs include an error. Successful file exports include a download URL; exports prepared for training cost estimates include a validation report and a null download URL. properties: createdAt: description: Time the export was requested, as an ISO 8601 timestamp. format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d:[0-5]\d(?:\.\d+)?(?:Z))$ type: string datasetId: $ref: '#/components/schemas/DatasetId' error: anyOf: - properties: code: description: >- Failure category: `empty_selection` when no rows match, `size_limit_exceeded` when the export is too large, or `assembly_failed` when preparation fails. enum: - empty_selection - size_limit_exceeded - assembly_failed type: string message: description: Explanation of why the export failed. maxLength: 500 minLength: 1 type: string timestamp: description: Time the export failed, as an ISO 8601 timestamp. format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d:[0-5]\d(?:\.\d+)?(?:Z))$ type: string required: - timestamp - code - message type: object - type: 'null' description: Failure details, or null when the export has not failed. id: $ref: '#/components/schemas/ExportId' report: anyOf: - $ref: '#/components/schemas/DatasetExportReport' - type: 'null' description: >- Training-example validation report, or null for ordinary file exports or before validation finishes. result: description: Download details for the export. properties: downloadUrl: description: >- Signed file download URL, or null before completion, after failure, or for validation-only exports. type: - string - 'null' required: - downloadUrl type: object status: description: >- Export state: `running` while preparing, `succeeded` when complete, or `failed` after an error. enum: - running - succeeded - failed type: string required: - id - datasetId - status - createdAt - result - report - error type: object ExportId: description: Dataset export ID with prefix `dex.`. pattern: >- ^dex\.[0-9a-f]{8}-[0-9a-f]{4}-[7][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$ type: string DatasetExportReport: additionalProperties: false description: >- Counts of rows included in or excluded from training examples, exclusion reasons, and token statistics. properties: errors: description: Sample of validation errors, up to 50 entries. items: additionalProperties: false properties: itemIndex: description: Index of the dataset item with a validation error. maximum: 9007199254740991 minimum: 0 type: integer reason: description: Reason the example failed validation. type: string required: - itemIndex - reason type: object maxItems: 50 type: array invalidCount: description: Number of examples rejected during validation. maximum: 9007199254740991 minimum: 0 type: integer tokens: additionalProperties: false description: Token-count statistics for the valid examples. properties: estimatorVersion: anyOf: - enum: - utf16-code-units-div-4-v1 - script-weighted-v1 type: string - type: 'null' description: >- Token estimator version used for these statistics, or null when unavailable. max: description: Largest token count among valid examples. maximum: 9007199254740991 minimum: 0 type: integer p50: description: Median number of tokens per valid example. maximum: 9007199254740991 minimum: 0 type: integer p95: description: 95th percentile of tokens per valid example. maximum: 9007199254740991 minimum: 0 type: integer total: anyOf: - maximum: 9007199254740991 minimum: 0 type: integer - type: 'null' default: null description: Total tokens across valid examples, or null when unavailable. required: - p50 - p95 - max - estimatorVersion type: object validCount: description: Number of valid training examples in the selection. maximum: 9007199254740991 minimum: 0 type: integer required: - validCount - invalidCount - errors - tokens type: object headers: RateLimit-Limit: description: The maximum number of requests allowed in the current window. schema: type: integer RateLimit-Policy: description: The rate limit policy (e.g., "60;w=60"). schema: type: string RateLimit-Remaining: description: The number of requests remaining in the current window. schema: type: integer RateLimit-Reset: description: The number of seconds until the current window resets. schema: type: integer X-Request-Id: description: >- The request id: the X-Request-Id you sent when it is 1-128 characters of letters, digits, ".", "_" or "-", otherwise a generated UUID. Present on every response, including errors; quote it when reporting a problem. schema: type: string securitySchemes: apiKeyAuth: description: >- Enter `ApiKey ` in Authorization, including the `ApiKey ` prefix. In cURL and Python samples, `` means this full value. The TypeScript SDK adds the prefix for you. in: header name: Authorization type: apiKey scopedTokenAuth: description: >- Enter the project-scoped token as `pst_...` in X-Scoped-Token, without an `ApiKey ` prefix. Create a token with POST /projects/{projectId}/tokens. in: header name: X-Scoped-Token type: apiKey ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.