> ## 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 file upload > Send `filename`, `declaredSizeBytes`, and an optional format and field mapping. Files may be up to 1 GiB. Returns an upload and `uploadUrl`. PUT the file bytes to that URL with the required `x-ms-blob-type: BlockBlob` header. After the PUT succeeds, finalize the upload. The file must not exceed its declared size. ## OpenAPI ````yaml /api-reference/openapi.json post /datasets/{datasetId}/uploads 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}/uploads: post: tags: - Dataset uploads summary: Start a dataset file upload description: >- Send `filename`, `declaredSizeBytes`, and an optional format and field mapping. Files may be up to 1 GiB. Returns an upload and `uploadUrl`. PUT the file bytes to that URL with the required `x-ms-blob-type: BlockBlob` header. After the PUT succeeds, finalize the upload. The file must not exceed its declared size. operationId: createDatasetUpload parameters: - in: path name: datasetId required: true schema: $ref: '#/components/schemas/DatasetId' requestBody: content: application/json: schema: properties: declaredSizeBytes: description: Declared maximum upload size in bytes, from 1 byte to 1 GiB. exclusiveMinimum: 0 maximum: 1073741824 type: integer fields: description: >- Additional fields to create from matching keys in uploaded rows. Each complete row is also stored in "uploaded"; existing profile mappings still apply. items: properties: jsonSchema: $ref: '#/components/schemas/JsonSchema' description: >- JSON Schema for the field values. Defaults to {} (accepts any value). name: description: Name of a dataset field to match to a key in each row. maxLength: 128 minLength: 1 pattern: ^[a-z]([a-z0-9_]*[a-z0-9])?$ type: string required: - name type: object type: array filename: description: Name of the file being uploaded. minLength: 1 type: string format: default: json description: >- File format: "json" (a JSON array of row objects), "jsonl" (one JSON object per line) or "csv" (a header row naming the fields, one row per item; all values are ingested as strings). Defaults to "json". enum: - json - csv - jsonl type: string required: - filename - declaredSizeBytes type: object responses: '200': content: application/json: schema: properties: job: $ref: '#/components/schemas/UploadJob' uploadUrl: description: >- Signed URL for uploading file bytes with a PUT request and the `x-ms-blob-type: BlockBlob` header. type: string required: - job - uploadUrl type: object description: Upload initiated 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' '409': description: Another upload is in progress 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: $ref: '#/components/headers/X-Request-Id' x-codeSamples: - label: TypeScript SDK lang: typescript source: | import { createClient } from "@toloka-platform/sdk"; const client = createClient({ baseUrl: "https://platform.toloka.ai", apiKey: process.env.TOLOKA_API_KEY!, }); const data = JSON.stringify([{ text: "Classify this sentence." }]); const upload = await client.datasets.startUpload({ datasetId: "ds.019a0000-0000-7000-8000-000000000001", filename: "examples.json", format: "json", declaredSizeBytes: new TextEncoder().encode(data).byteLength }); console.log(upload); components: schemas: DatasetId: description: Dataset ID with prefix `ds.`. pattern: >- ^ds\.[0-9a-f]{8}-[0-9a-f]{4}-[7][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$ type: string JsonSchema: additionalProperties: false description: JSON Schema defining the accepted values for a field. properties: additionalProperties: anyOf: - description: >- Whether extra object properties are allowed, or the schema they must satisfy; omitted means allowed. type: boolean - $ref: '#/components/schemas/JsonSchema' description: >- Whether extra object properties are allowed, or the schema they must satisfy; omitted means allowed. description: >- Whether extra object properties are allowed, or the schema they must satisfy; omitted means allowed. allOf: description: Combined schemas; a value must satisfy every schema when supplied. items: $ref: '#/components/schemas/JsonSchema' description: JSON Schema defining the accepted values for a field. minItems: 1 type: array anyOf: description: >- Alternative schemas; a value must satisfy at least one when supplied. items: $ref: '#/components/schemas/JsonSchema' description: JSON Schema defining the accepted values for a field. minItems: 1 type: array const: $ref: '#/components/schemas/JsonValue' description: Single required JSON value; omit when no exact value is required. default: $ref: '#/components/schemas/JsonValue' description: Suggested default JSON value; omit when none is specified. description: description: Optional explanation of the values accepted by this schema. type: string enum: description: >- Allowed JSON values; omit to allow any value satisfying the other constraints. items: $ref: '#/components/schemas/JsonValue' minItems: 1 type: array examples: description: Example JSON values for this schema; omit when none are supplied. items: $ref: '#/components/schemas/JsonValue' type: array exclusiveMaximum: description: Exclusive upper bound for a number; omit when none is required. type: number exclusiveMinimum: description: Exclusive lower bound for a number; omit when none is required. type: number format: description: >- String format, such as `date-time`, `email`, or `uri`; omit when no format is required. type: string items: $ref: '#/components/schemas/JsonSchema' description: >- Schema that every array item must satisfy; omit to leave items unrestricted. maxItems: description: Maximum number of array items; omit for no upper bound. maximum: 9007199254740991 minimum: 0 type: integer maxLength: description: >- Maximum string length in Unicode characters; omit for no upper bound. maximum: 9007199254740991 minimum: 0 type: integer maximum: description: Inclusive upper bound for a number; omit for no upper bound. type: number minItems: description: Minimum number of array items; omit for no lower bound. maximum: 9007199254740991 minimum: 0 type: integer minLength: description: >- Minimum string length in Unicode characters; omit for no lower bound. maximum: 9007199254740991 minimum: 0 type: integer minimum: description: Inclusive lower bound for a number; omit for no lower bound. type: number oneOf: description: Alternative schemas; a value must satisfy exactly one when supplied. items: $ref: '#/components/schemas/JsonSchema' description: JSON Schema defining the accepted values for a field. minItems: 1 type: array pattern: description: >- Regular expression a string must match; omit for no pattern constraint. type: string properties: $ref: '#/components/schemas/JsonSchemaProperties' description: Schemas for named object properties; omit when none are specified. required: description: >- Object property names that must be present; omit when none are required. items: type: string type: array title: description: Optional display title for this schema. type: string type: anyOf: - description: Accepted JSON type or types; omit to allow any type. enum: - string - number - integer - boolean - object - array - 'null' type: string - description: Accepted JSON type or types; omit to allow any type. items: enum: - string - number - integer - boolean - object - array - 'null' type: string minItems: 1 type: array description: Accepted JSON type or types; omit to allow any type. uniqueItems: description: >- Whether array items must be unique; omitted means duplicates are allowed. type: boolean type: object UploadJob: description: >- A dataset upload and its import status. After finalizing, poll until `status` is `succeeded` or `failed`. properties: createdAt: description: Time the upload was started, as an ISO 8601 timestamp. format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d:[0-5]\d(?:\.\d+)?(?:Z))$ type: string error: description: Failure or cancellation message, or null when no error is recorded. type: - string - 'null' id: $ref: '#/components/schemas/UploadId' result: description: Progress of the dataset import. properties: itemsIngested: description: >- Number of rows imported so far, including rows imported before a partial failure. example: 0 maximum: 9007199254740991 minimum: -9007199254740991 type: integer required: - itemsIngested type: object status: description: >- Upload state: `pending` before finalization, `running` while rows are imported, `succeeded` when complete, or `failed` after failure or cancellation. enum: - pending - running - succeeded - failed type: string required: - id - status - createdAt - error - result type: object JsonValue: anyOf: - type: string - type: number - type: boolean - type: 'null' - items: $ref: '#/components/schemas/JsonValue' type: array - additionalProperties: $ref: '#/components/schemas/JsonValue' propertyNames: type: string type: object JsonSchemaProperties: additionalProperties: $ref: '#/components/schemas/JsonSchema' propertyNames: type: string type: object UploadId: description: Dataset upload ID with prefix `dfu.`. pattern: >- ^dfu\.[0-9a-f]{8}-[0-9a-f]{4}-[7][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$ type: string 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.