Foundation Models Text Generation API, REST: TextGenerationAsync.Completion

A method for generating text completions in asynchronous mode.

HTTP request

POST https://llm.api.cloud.yandex.net/foundationModels/v1/completionAsync

Body parameters

{
          "modelUri": "string",
          "completionOptions": {
            "stream": "boolean",
            "temperature": "number",
            "maxTokens": "string",
            "reasoningOptions": {
              "mode": "string"
            }
          },
          "messages": [
            {
              "role": "string",
              // Includes only one of the fields `text`, `toolCallList`, `toolResultList`
              "text": "string",
              "toolCallList": {
                "toolCalls": [
                  {
                    // Includes only one of the fields `functionCall`
                    "functionCall": {
                      "name": "string",
                      "arguments": "object"
                    }
                    // end of the list of possible fields
                  }
                ]
              },
              "toolResultList": {
                "toolResults": [
                  {
                    // Includes only one of the fields `functionResult`
                    "functionResult": {
                      "name": "string",
                      // Includes only one of the fields `content`
                      "content": "string"
                      // end of the list of possible fields
                    }
                    // end of the list of possible fields
                  }
                ]
              }
              // end of the list of possible fields
            }
          ],
          "tools": [
            {
              // Includes only one of the fields `function`
              "function": {
                "name": "string",
                "description": "string",
                "parameters": "object",
                "strict": "boolean"
              }
              // end of the list of possible fields
            }
          ],
          // Includes only one of the fields `jsonObject`, `jsonSchema`
          "jsonObject": "boolean",
          "jsonSchema": {
            "schema": "object"
          },
          // end of the list of possible fields
          "parallelToolCalls": "boolean",
          "toolChoice": {
            // Includes only one of the fields `mode`, `functionName`
            "mode": "string",
            "functionName": "string"
            // end of the list of possible fields
          }
        }

Request for the service to generate text completion.

Field	Description
modelUri	string The ID of the model to be used for completion generation.
completionOptions	CompletionOptions Configuration options for completion generation.
messages[]	Message A list of messages representing the context for the completion model.
tools[]	Tool List of tools that are available for the model to invoke during the completion generation. Note: This parameter is not yet supported and will be ignored if provided.
jsonObject	boolean When set to true, the model will respond with a valid JSON object. Be sure to explicitly ask the model for JSON. Otherwise, it may generate excessive whitespace and run indefinitely until it reaches the token limit. Includes only one of the fields `jsonObject`, `jsonSchema`. Specifies the format of the model's response.
jsonSchema	JsonSchema Enforces a specific JSON structure for the model's response based on a provided schema. Includes only one of the fields `jsonObject`, `jsonSchema`. Specifies the format of the model's response.
parallelToolCalls	boolean Controls whether the model can generate multiple tool calls in a single response. Defaults to true.
toolChoice	ToolChoice Specifies how the model should select which tool (or tools) to use when generating a response.

CompletionOptions

Defines the options for completion generation.

Field	Description
stream	boolean Enables streaming of partially generated text.
temperature	number (double) Affects creativity and randomness of responses. Should be a double number between 0 (inclusive) and 1 (inclusive). Lower values produce more straightforward responses while higher values lead to increased creativity and randomness. Default temperature: 0.3
maxTokens	string (int64) The limit on the number of tokens used for single completion generation. Must be greater than zero. This maximum allowed parameter value may depend on the model being used.
reasoningOptions	ReasoningOptions Configures reasoning capabilities for the model, allowing it to perform internal reasoning before responding.

ReasoningOptions

Represents reasoning options that enable the model's ability to perform internal reasoning before generating a response.

Field

Description

mode

enum (ReasoningMode)

Specifies the reasoning mode to be used.

REASONING_MODE_UNSPECIFIED: Unspecified reasoning mode.
DISABLED: Disables reasoning. The model will generate a response without performing any internal reasoning.
ENABLED_HIDDEN: Enables reasoning in a hidden manner without exposing the reasoning steps to the user.

Message

A message object representing a wrapper over the inputs and outputs of the completion model.

Field	Description
role	string The ID of the message sender. Supported roles: `system`: Special role used to define the behavior of the completion model. `assistant`: A role used by the model to generate responses. `user`: A role used by the user to describe requests to the model.
text	string Textual content of the message. Includes only one of the fields `text`, `toolCallList`, `toolResultList`. Message content.
toolCallList	ToolCallList List of tool calls made by the model as part of the response generation. Includes only one of the fields `text`, `toolCallList`, `toolResultList`. Message content.
toolResultList	ToolResultList List of tool results returned from external tools that were invoked by the model. Includes only one of the fields `text`, `toolCallList`, `toolResultList`. Message content.

ToolCallList

Represents a list of tool calls.

Field

Description

toolCalls[]

ToolCall

A list of tool calls to be executed.

ToolCall

Represents a call to a tool.

Field

Description

functionCall

FunctionCall

Represents a call to a function.

Includes only one of the fields functionCall.

FunctionCall

Represents the invocation of a function with specific arguments.

Field

Description

name

string

The name of the function being called.

arguments

object

The structured arguments passed to the function.
These arguments must adhere to the JSON Schema defined in the corresponding function's parameters.

ToolResultList

Represents a list of tool results.

Field

Description

toolResults[]

ToolResult

A list of tool results.

ToolResult

Represents the result of a tool call.

Field

Description

functionResult

FunctionResult

Represents the result of a function call.

Includes only one of the fields functionResult.

FunctionResult

Represents the result of a function call.

Field

Description

name

string

The name of the function that was executed.

content

string

The result of the function call, represented as a string.
This field can be used to store the output of the function.

Includes only one of the fields content.

Tool

Represents a tool that can be invoked during completion generation.

Field

Description

function

FunctionTool

Represents a function that can be called.

Includes only one of the fields function.

FunctionTool

Represents a function tool that can be invoked during completion generation.

Field	Description
name	string The name of the function.
description	string A description of the function's purpose or behavior.
parameters	object A JSON Schema that defines the expected parameters for the function. The schema should describe the required fields, their types, and any constraints or default values.
strict	boolean Enforces strict adherence to the function schema, ensuring only defined parameters are used.

JsonSchema

Represents the expected structure of the model's response using a JSON Schema.

Field

Description

schema

object

The JSON Schema that the model's output must conform to.

ToolChoice

Specifies how the model should select which tool (or tools) to use when generating a response.

Field

Description

mode

enum (ToolChoiceMode)

Specifies the overall tool-calling mode.

Includes only one of the fields mode, functionName.

TOOL_CHOICE_MODE_UNSPECIFIED: The server will choose the default behavior, which is AUTO.
NONE: The model will not call any tool and will generate a standard text response.
AUTO: The model can choose between generating a text response or calling one or more tools.
This is the default behavior.
REQUIRED: The model is required to call one or more tools.

functionName

string

Forces the model to call a specific function.
The provided string must match the name of a function in the API request.

Includes only one of the fields mode, functionName.

Response

HTTP Code: 200 - OK

{
          "id": "string",
          "description": "string",
          "createdAt": "string",
          "createdBy": "string",
          "modifiedAt": "string",
          "done": "boolean",
          "metadata": "object",
          // Includes only one of the fields `error`, `response`
          "error": {
            "code": "integer",
            "message": "string",
            "details": [
              "object"
            ]
          },
          "response": {
            "alternatives": [
              {
                "message": {
                  "role": "string",
                  // Includes only one of the fields `text`, `toolCallList`, `toolResultList`
                  "text": "string",
                  "toolCallList": {
                    "toolCalls": [
                      {
                        // Includes only one of the fields `functionCall`
                        "functionCall": {
                          "name": "string",
                          "arguments": "object"
                        }
                        // end of the list of possible fields
                      }
                    ]
                  },
                  "toolResultList": {
                    "toolResults": [
                      {
                        // Includes only one of the fields `functionResult`
                        "functionResult": {
                          "name": "string",
                          // Includes only one of the fields `content`
                          "content": "string"
                          // end of the list of possible fields
                        }
                        // end of the list of possible fields
                      }
                    ]
                  }
                  // end of the list of possible fields
                },
                "status": "string"
              }
            ],
            "usage": {
              "inputTextTokens": "string",
              "completionTokens": "string",
              "totalTokens": "string",
              "completionTokensDetails": {
                "reasoningTokens": "string"
              }
            },
            "modelVersion": "string"
          }
          // end of the list of possible fields
        }

An Operation resource. For more information, see Operation.

Field	Description
id	string ID of the operation.
description	string Description of the operation. 0-256 characters long.
createdAt	string (date-time) Creation timestamp. String in RFC3339 text format. The range of possible values is from `0001-01-01T00:00:00Z` to `9999-12-31T23:59:59.999999999Z`, i.e. from 0 to 9 digits for fractions of a second. To work with values in this field, use the APIs described in the Protocol Buffers reference. In some languages, built-in datetime utilities do not support nanosecond precision (9 digits).
createdBy	string ID of the user or service account who initiated the operation.
modifiedAt	string (date-time) The time when the Operation resource was last modified. String in RFC3339 text format. The range of possible values is from `0001-01-01T00:00:00Z` to `9999-12-31T23:59:59.999999999Z`, i.e. from 0 to 9 digits for fractions of a second. To work with values in this field, use the APIs described in the Protocol Buffers reference. In some languages, built-in datetime utilities do not support nanosecond precision (9 digits).
done	boolean If the value is `false`, it means the operation is still in progress. If `true`, the operation is completed, and either `error` or `response` is available.
metadata	object Service-specific metadata associated with the operation. It typically contains the ID of the target resource that the operation is performed on. Any method that returns a long-running operation should document the metadata type, if any.
error	Status The error result of the operation in case of failure or cancellation. Includes only one of the fields `error`, `response`. The operation result. If `done == false` and there was no failure detected, neither `error` nor `response` is set. If `done == false` and there was a failure detected, `error` is set. If `done == true`, exactly one of `error` or `response` is set.
response	CompletionResponse The normal response of the operation in case of success. If the original method returns no data on success, such as Delete, the response is google.protobuf.Empty. If the original method is the standard Create/Update, the response should be the target resource of the operation. Any method that returns a long-running operation should document the response type, if any. Includes only one of the fields `error`, `response`. The operation result. If `done == false` and there was no failure detected, neither `error` nor `response` is set. If `done == false` and there was a failure detected, `error` is set. If `done == true`, exactly one of `error` or `response` is set.

Status

The error result of the operation in case of failure or cancellation.

Field	Description
code	integer (int32) Error code. An enum value of google.rpc.Code.
message	string An error message.
details[]	object A list of messages that carry the error details.

CompletionResponse

Response containing generated text completions.

Field	Description
alternatives[]	Alternative A list of generated completion alternatives.
usage	ContentUsage A set of statistics describing the number of content tokens used by the completion model.
modelVersion	string The model version changes with each new releases.

Alternative

Represents a generated completion alternative, including its content and generation status.

Field

Description

message

Message

A message with the content of the alternative.

status

enum (AlternativeStatus)

The generation status of the alternative.

ALTERNATIVE_STATUS_UNSPECIFIED: Unspecified generation status.
ALTERNATIVE_STATUS_PARTIAL: Partially generated alternative.
ALTERNATIVE_STATUS_TRUNCATED_FINAL: Incomplete final alternative resulting from reaching the maximum allowed number of tokens.
ALTERNATIVE_STATUS_FINAL: Final alternative generated without running into any limits.
ALTERNATIVE_STATUS_CONTENT_FILTER: Generation was stopped due to the discovery of potentially sensitive content in the prompt or generated response.
To fix, modify the prompt and restart generation.
ALTERNATIVE_STATUS_TOOL_CALLS: Tools were invoked during the completion generation.

Message

A message object representing a wrapper over the inputs and outputs of the completion model.

Field	Description
role	string The ID of the message sender. Supported roles: `system`: Special role used to define the behavior of the completion model. `assistant`: A role used by the model to generate responses. `user`: A role used by the user to describe requests to the model.
text	string Textual content of the message. Includes only one of the fields `text`, `toolCallList`, `toolResultList`. Message content.
toolCallList	ToolCallList List of tool calls made by the model as part of the response generation. Includes only one of the fields `text`, `toolCallList`, `toolResultList`. Message content.
toolResultList	ToolResultList List of tool results returned from external tools that were invoked by the model. Includes only one of the fields `text`, `toolCallList`, `toolResultList`. Message content.

ToolCallList

Represents a list of tool calls.

Field

Description

toolCalls[]

ToolCall

A list of tool calls to be executed.

ToolCall

Represents a call to a tool.

Field

Description

functionCall

FunctionCall

Represents a call to a function.

Includes only one of the fields functionCall.

FunctionCall

Represents the invocation of a function with specific arguments.

Field

Description

name

string

The name of the function being called.

arguments

object

The structured arguments passed to the function.
These arguments must adhere to the JSON Schema defined in the corresponding function's parameters.

ToolResultList

Represents a list of tool results.

Field

Description

toolResults[]

ToolResult

A list of tool results.

ToolResult

Represents the result of a tool call.

Field

Description

functionResult

FunctionResult

Represents the result of a function call.

Includes only one of the fields functionResult.

FunctionResult

Represents the result of a function call.

Field

Description

name

string

The name of the function that was executed.

content

string

The result of the function call, represented as a string.
This field can be used to store the output of the function.

Includes only one of the fields content.

ContentUsage

An object representing the number of content tokens used by the completion model.

Field	Description
inputTextTokens	string (int64) The number of tokens in the textual part of the model input.
completionTokens	string (int64) The number of tokens in the generated completion.
totalTokens	string (int64) The total number of tokens, including all input tokens and all generated tokens.
completionTokensDetails	CompletionTokensDetails Provides additional information about how the completion tokens were utilized.

CompletionTokensDetails

Provides additional information about how the completion tokens were utilized.

Field

Description

reasoningTokens

string (int64)

The number of tokens used specifically for internal reasoning performed by the model.

Was the article helpful?

Overview

Foundation Models Text Generation API, REST: TextGenerationAsync.Completion

HTTP requestHTTP request

Body parametersBody parameters

CompletionOptionsCompletionOptions

ReasoningOptionsReasoningOptions

MessageMessage

ToolCallListToolCallList

ToolCallToolCall

FunctionCallFunctionCall

ToolResultListToolResultList

ToolResultToolResult

FunctionResultFunctionResult

ToolTool

FunctionToolFunctionTool

JsonSchemaJsonSchema

ToolChoiceToolChoice

ResponseResponse

StatusStatus

CompletionResponseCompletionResponse

AlternativeAlternative

MessageMessage

ToolCallListToolCallList

ToolCallToolCall

FunctionCallFunctionCall

ToolResultListToolResultList

ToolResultToolResult

FunctionResultFunctionResult

ContentUsageContentUsage

CompletionTokensDetailsCompletionTokensDetails

Was the article helpful?

HTTP request

Body parameters

CompletionOptions

ReasoningOptions

Message

ToolCallList

ToolCall

FunctionCall

ToolResultList

ToolResult

FunctionResult

Tool

FunctionTool

JsonSchema

ToolChoice

Response

Status

CompletionResponse

Alternative

Message

ToolCallList

ToolCall

FunctionCall

ToolResultList

ToolResult

FunctionResult

ContentUsage

CompletionTokensDetails