> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dify.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Update Document Metadata in Batch

> Update metadata values for multiple documents at once. Each document in the request receives the specified metadata key-value pairs.



## OpenAPI

````yaml /en/api-reference/openapi_knowledge.json post /datasets/{dataset_id}/documents/metadata
openapi: 3.0.1
info:
  title: Knowledge API
  description: >-
    API for managing knowledge bases, documents, chunks, metadata, and tags,
    including creation, retrieval, and configuration. **Note:** A single
    Knowledge Base API key has permission to operate on all visible knowledge
    bases under the same account. Please pay attention to data security.
  version: 1.0.0
servers:
  - url: '{apiBaseUrl}'
    description: The base URL for the Knowledge API.
    variables:
      apiBaseUrl:
        default: https://api.dify.ai/v1
        description: Actual base URL of the API
security:
  - ApiKeyAuth: []
tags:
  - name: Knowledge Bases
    description: >-
      Operations for managing knowledge bases, including creation,
      configuration, and retrieval.
  - name: Documents
    description: >-
      Operations for creating, updating, and managing documents within a
      knowledge base.
  - name: Chunks
    description: Operations for managing document chunks and child chunks.
  - name: Metadata
    description: >-
      Operations for managing knowledge base metadata fields and document
      metadata values.
  - name: Tags
    description: Operations for managing knowledge base tags and tag bindings.
  - name: Models
    description: Operations for retrieving available models.
  - name: Knowledge Pipeline
    description: >-
      Operations for managing and running knowledge pipelines, including
      datasource plugins and pipeline execution.
paths:
  /datasets/{dataset_id}/documents/metadata:
    post:
      tags:
        - Metadata
      summary: Update Document Metadata in Batch
      description: >-
        Update metadata values for multiple documents at once. Each document in
        the request receives the specified metadata key-value pairs.
      operationId: batchUpdateDocumentMetadata
      parameters:
        - name: dataset_id
          in: path
          required: true
          schema:
            type: string
            format: uuid
          description: Knowledge base ID.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - operation_data
              properties:
                operation_data:
                  type: array
                  items:
                    type: object
                    required:
                      - document_id
                      - metadata_list
                    properties:
                      document_id:
                        type: string
                        description: ID of the document whose metadata to update.
                      metadata_list:
                        type: array
                        items:
                          type: object
                          required:
                            - id
                            - name
                          properties:
                            id:
                              type: string
                              description: Metadata field ID.
                            name:
                              type: string
                              description: Metadata field name.
                            value:
                              description: >-
                                Metadata value. Can be a string, number, or
                                `null`.
                      partial_update:
                        type: boolean
                        default: false
                        description: >-
                          Whether to partially update metadata, keeping existing
                          values for unspecified fields.
                  description: >-
                    Array of document metadata update operations. Each entry
                    maps a document ID to its metadata key-value pairs.
      responses:
        '200':
          description: Document metadata updated successfully.
          content:
            application/json:
              schema:
                type: object
                properties:
                  result:
                    type: string
                    description: Operation result.
              examples:
                success:
                  summary: Response Example
                  value:
                    result: success
components:
  securitySchemes:
    ApiKeyAuth:
      type: http
      scheme: bearer
      bearerFormat: API_KEY
      description: >-
        API Key authentication. For all API requests, include your API Key in
        the `Authorization` HTTP Header, prefixed with `Bearer `. Example:
        `Authorization: Bearer {API_KEY}`. **Strongly recommend storing your API
        Key on the server-side, not shared or stored on the client-side, to
        avoid possible API-Key leakage that can lead to serious consequences.**

````