> ## 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 Sync Policy

> Sets a source's sync schedule, replacing the previous one, and returns it.

Saving does not start a sync. The first scheduled sync is due one interval after the update, and each later one an interval after the previous one was queued. To sync now, call [Sync Source](/en/api-reference/source-syncs-and-imports/sync-source).

After each import into the source finishes, save the schedule again with the source's new `version`. An import changes `version`, and a schedule still bound to the old one turns itself off at its next due time.

To pause scheduled syncs without changing the schedule, set the source's `status` to `disabled` with [Update Source](/en/api-reference/sources/update-source). A sync that came due meanwhile runs when the source is set back to `active`.

For the read-then-save flow, see [Sync and Schedule Sources](/en/api-reference/guides/knowledge-base#sync-and-schedule-sources).



## OpenAPI

````yaml /en/api-reference/openapi_service.json put /knowledge-fs/spaces/{knowledge_base_id}/sources/{source_id}/sync-policy
openapi: 3.0.1
info:
  description: >-
    REST API for Dify applications and knowledge bases. Application endpoints
    authenticate with an app API key; knowledge endpoints authenticate with a
    dataset API key.
  title: Dify Service API
  version: 1.0.0
servers:
  - description: >-
      Base URL of the Dify Service API. For self-hosted deployments, replace it
      with your own API base URL.
    url: https://{api_base_url}
    variables:
      api_base_url:
        default: api.dify.ai/v1
        description: Host and path of the API base URL, without the `https://` prefix.
security:
  - ApiKeyAuth: []
tags:
  - description: Operations related to chat messages and interactions.
    name: Chat Messages
  - description: File upload and preview operations.
    name: Files
  - description: Operations related to end user information.
    name: End Users
  - description: User feedback operations.
    name: Feedback
  - description: Operations related to managing conversations.
    name: Conversations
  - description: Text-to-Speech and Speech-to-Text operations.
    name: Audio
  - description: Operations to retrieve application settings and information.
    name: Applications
  - description: Operations related to managing annotations for direct replies.
    name: Annotations
  - description: Endpoints for resuming paused workflows that require human input.
    name: Human Input
  - description: Operations for executing and managing workflows.
    name: Workflow Runs
  - description: Operations related to text generation and completion.
    name: Completion Messages
  - description: >-
      Operations for managing knowledge bases, including creation,
      configuration, and retrieval.
    name: Knowledge Bases
  - description: >-
      Operations for creating, updating, and managing documents within a
      knowledge base.
    name: Documents
  - description: Operations for managing document chunks and child chunks.
    name: Chunks
  - description: >-
      Operations for managing knowledge base metadata fields and document
      metadata values.
    name: Metadata
  - description: Operations for managing knowledge base tags and tag bindings.
    name: Tags
  - description: Operations for retrieving available models.
    name: Models
  - description: >-
      Operations for managing and running knowledge pipelines, including
      datasource plugins and pipeline execution.
    name: Knowledge Pipeline
  - description: Ask a knowledge base a question and stream the answer.
    name: Queries
  - description: Inspect what a query retrieved and why.
    name: Query Records
  - description: Run a research question in the background and collect its results.
    name: Research Tasks
  - description: >-
      Read the documents in a knowledge base, their files, revisions, and
      chunks; label documents with metadata.
    name: Documents and Chunks
  - description: >-
      Follow, cancel, or retry indexing, and list the knowledge base's
      background tasks.
    name: Indexing Tasks
  - description: >-
      Follow the deletion of a document file, a batch of files, or a source
      until it finishes.
    name: Deletion Jobs
  - description: >-
      Manage the sources that feed a knowledge base, their sync schedules, and
      their connections.
    name: Sources
  - description: >-
      Sync a source now, import website pages or provider items, and follow,
      cancel, or retry the runs.
    name: Source Syncs and Imports
  - description: >-
      Read and change the knowledge base's models and retrieval settings, and
      follow the migration a change starts.
    name: Settings
paths:
  /knowledge-fs/spaces/{knowledge_base_id}/sources/{source_id}/sync-policy:
    put:
      tags:
        - Sources
      summary: Update Sync Policy
      description: >-
        Sets a source's sync schedule, replacing the previous one, and returns
        it.


        Saving does not start a sync. The first scheduled sync is due one
        interval after the update, and each later one an interval after the
        previous one was queued. To sync now, call [Sync
        Source](/en/api-reference/source-syncs-and-imports/sync-source).


        After each import into the source finishes, save the schedule again with
        the source's new `version`. An import changes `version`, and a schedule
        still bound to the old one turns itself off at its next due time.


        To pause scheduled syncs without changing the schedule, set the source's
        `status` to `disabled` with [Update
        Source](/en/api-reference/sources/update-source). A sync that came due
        meanwhile runs when the source is set back to `active`.


        For the read-then-save flow, see [Sync and Schedule
        Sources](/en/api-reference/guides/knowledge-base#sync-and-schedule-sources).
      operationId: updateSourceSyncPolicy
      parameters:
        - description: >-
            Knowledge base ID: the last segment of the Service API endpoint
            shown in the knowledge base's **API Access** dialog
            (`…/knowledge-fs/spaces/<knowledge base ID>`), and the segment after
            `/datasets/new/` in the address bar.
          in: path
          name: knowledge_base_id
          required: true
          schema:
            format: uuid
            type: string
        - description: >-
            Source ID. From [List
            Sources](/en/api-reference/sources/list-sources).
          in: path
          name: source_id
          required: true
          schema:
            format: uuid
            type: string
      requestBody:
        content:
          application/json:
            examples:
              custom:
                summary: Request Example - Custom interval
                value:
                  customIntervalSeconds: 21600
                  enabled: true
                  expectedRevision: 5
                  expectedSourceVersion: 8
                  mode: custom
              interval:
                summary: Request Example - Every 24 hours
                value:
                  enabled: true
                  expectedRevision: 0
                  expectedSourceVersion: 3
                  mode: interval
              manual:
                summary: Request Example - No schedule
                value:
                  enabled: false
                  expectedRevision: 6
                  expectedSourceVersion: 8
                  mode: manual
            schema:
              additionalProperties: false
              properties:
                customIntervalSeconds:
                  description: >-
                    Seconds between scheduled syncs, from 1 hour to 30 days.
                    Required with `mode: custom` and rejected with the other
                    modes.
                  maximum: 2592000
                  minimum: 3600
                  type: integer
                enabled:
                  description: >-
                    Whether scheduled syncs run. Must be `false` with `mode:
                    manual`.
                  type: boolean
                expectedRevision:
                  description: >-
                    The schedule's current `revision`, from [Get Sync
                    Policy](/en/api-reference/sources/get-sync-policy). Send `0`
                    when the source has no schedule yet. The revision also
                    increases every time a scheduled sync starts, so read it
                    right before updating. A stale value answers `409` and
                    nothing changes.
                  minimum: 0
                  type: integer
                expectedSourceVersion:
                  description: >-
                    The source's current `version`, from [Get
                    Source](/en/api-reference/sources/get-source) or [List
                    Sources](/en/api-reference/sources/list-sources). It changes
                    after every [Update
                    Source](/en/api-reference/sources/update-source) call and
                    every completed import, so read it right before updating. A
                    stale value answers `409` and nothing changes.
                  minimum: 1
                  type: integer
                mode:
                  description: >-
                    `manual` turns scheduled syncs off, `interval` syncs every
                    24 hours, and `custom` syncs every `customIntervalSeconds`.
                  enum:
                    - manual
                    - interval
                    - custom
                  type: string
              required:
                - enabled
                - expectedRevision
                - expectedSourceVersion
                - mode
              type: object
        required: true
      responses:
        '200':
          content:
            application/json:
              examples:
                success:
                  summary: Response Example
                  value:
                    created_at: '2026-09-01T08:05:00Z'
                    custom_interval_seconds: 21600
                    enabled: true
                    expected_source_version: 8
                    id: 8e7d6c5b-4a39-4f28-9e17-0d1c2b3a4f5e
                    knowledge_space_id: 0a9d3c2e-5b6f-4e1a-8c7d-2f3e4a5b6c7d
                    mode: custom
                    next_run_at: '2026-10-21T08:30:00Z'
                    revision: 6
                    source_id: 6f1c2b0e-3d0b-4a5e-9f4c-1c0e6a7b8d90
                    updated_at: '2026-10-21T02:30:00Z'
              schema:
                $ref: '#/components/schemas/KnowledgeBaseSyncPolicy'
          description: >-
            The saved schedule. With `mode: manual` or `enabled: false`,
            `next_run_at` is `null`.
        '400':
          content:
            application/json:
              examples:
                knowledge_fs_invalid_request_local:
                  summary: knowledge_fs_invalid_request (request validation)
                  value:
                    code: knowledge_fs_invalid_request
                    message: Agent Knowledge Base request is invalid.
                    status: 400
                    violations:
                      - field:
                          - customIntervalSeconds
                        type: greater_than_equal
                knowledge_fs_invalid_request_path:
                  summary: knowledge_fs_invalid_request (path ID)
                  value:
                    code: knowledge_fs_invalid_request
                    message: Agent Knowledge Base request is invalid.
                    status: 400
                knowledge_fs_invalid_request_upstream:
                  summary: knowledge_fs_invalid_request (rejected)
                  value:
                    code: knowledge_fs_invalid_request
                    failure:
                      category: validation
                      code: KNOWLEDGE_FS_INVALID_REQUEST
                      message: The Agent Knowledge Base request is invalid.
                      retryPolicy: never
                      traceId: 7f3c1a90-2e64-4b7d-8a51-6c0d9e2f4b83
                    message: The Agent Knowledge Base request is invalid.
                    status: 400
          description: >-
            - `knowledge_fs_invalid_request`: the request failed validation.
            `violations` names each failing field. Causes:
              - A field is missing or of the wrong type, or the body carries an unknown key.
              - `mode` is not one of the listed values.
              - `customIntervalSeconds` is out of range, missing with `mode: custom`, or sent with another mode.
            - `knowledge_fs_invalid_request`: `mode: manual` was sent with
            `enabled: true`, or `source_id` is not a UUID.

            - `knowledge_fs_invalid_request`: `source_id` is malformed.
        '401':
          content:
            application/json:
              examples:
                knowledge_fs_invalid_credential:
                  summary: knowledge_fs_invalid_credential
                  value:
                    code: knowledge_fs_invalid_credential
                    message: Invalid Agent Knowledge Base service credential.
                    status: 401
                unauthorized:
                  summary: unauthorized
                  value:
                    code: unauthorized
                    message: Access token is invalid
                    status: 401
          description: >-
            - `unauthorized`: the `Authorization` header is missing, or the key
            is unknown or not a knowledge base API key.

            - `knowledge_fs_invalid_credential`: the key is valid, but no
            knowledge base with this ID exists in the key's workspace, or the
            key is not tied to a workspace.
        '403':
          content:
            application/json:
              examples:
                forbidden:
                  summary: forbidden (rate limit)
                  value:
                    code: forbidden
                    message: >-
                      Sorry, you have reached the knowledge base request rate
                      limit of your subscription.
                    status: 403
                knowledge_fs_access_denied_scope:
                  summary: knowledge_fs_access_denied (key scope)
                  value:
                    code: knowledge_fs_access_denied
                    message: Agent Knowledge Base operation is not allowed.
                    status: 403
          description: >-
            - `knowledge_fs_access_denied`: the key is scoped to other knowledge
            bases, **API access** is off for this knowledge base, or the
            knowledge base is not active.

            - `forbidden`: on Dify Cloud, the workspace has reached the
            knowledge base request rate limit of its subscription. Every call
            counts, reads included.
        '404':
          content:
            application/json:
              examples:
                knowledge_fs_resource_not_found:
                  summary: knowledge_fs_resource_not_found
                  value:
                    code: knowledge_fs_resource_not_found
                    failure:
                      category: not_found
                      code: KNOWLEDGE_FS_NOT_FOUND
                      message: >-
                        The requested Agent Knowledge Base resource was not
                        found.
                      retryPolicy: never
                      traceId: 7f3c1a90-2e64-4b7d-8a51-6c0d9e2f4b83
                    message: The requested Agent Knowledge Base resource was not found.
                    status: 404
                not_found:
                  summary: not_found (feature off)
                  value:
                    code: not_found
                    message: >-
                      The requested URL was not found on the server. If you
                      entered the URL manually please check your spelling and
                      try again.
                    status: 404
          description: >-
            - `knowledge_fs_resource_not_found`: no source with this ID exists
            in the knowledge base, the key cannot read it, or its deletion has
            been accepted.

            - `not_found`: the Agent Knowledge Base feature is turned off on
            this deployment.
        '409':
          content:
            application/json:
              examples:
                knowledge_fs_conflict:
                  summary: knowledge_fs_conflict
                  value:
                    code: knowledge_fs_conflict
                    failure:
                      action: retry
                      category: conflict
                      code: KNOWLEDGE_FS_CONFLICT
                      message: >-
                        The Agent Knowledge Base operation conflicts with the
                        current resource state.
                      retryPolicy: manual
                      traceId: 7f3c1a90-2e64-4b7d-8a51-6c0d9e2f4b83
                    message: >-
                      The Agent Knowledge Base operation conflicts with the
                      current resource state.
                    status: 409
          description: >-
            - `knowledge_fs_conflict`: `expectedRevision` is not the schedule's
            current `revision`, or `expectedSourceVersion` is not the source's
            current `version`. The body does not say which, so read both again
            with [Get Sync Policy](/en/api-reference/sources/get-sync-policy)
            and [Get Source](/en/api-reference/sources/get-source), then resend.
        '502':
          content:
            application/json:
              examples:
                knowledge_fs_upstream_unavailable:
                  summary: knowledge_fs_upstream_unavailable (service error)
                  value:
                    code: knowledge_fs_upstream_unavailable
                    failure:
                      action: contact_admin
                      category: internal
                      code: KNOWLEDGE_FS_INTERNAL_ERROR
                      message: >-
                        Agent Knowledge Base could not complete the operation.
                        Try again, or contact an administrator with the error
                        reference.
                      retryPolicy: manual
                      traceId: 5e2a9c17-3b4d-4f60-8a1b-2c3d4e5f6a7b
                    message: >-
                      Agent Knowledge Base could not complete the operation. Try
                      again, or contact an administrator with the error
                      reference.
                    status: 502
                knowledge_fs_upstream_unavailable_transport:
                  summary: knowledge_fs_upstream_unavailable (no response)
                  value:
                    code: knowledge_fs_upstream_unavailable
                    message: Agent Knowledge Base is unavailable.
                    status: 502
          description: >-
            - `knowledge_fs_upstream_unavailable`: no answer came back in time,
            or the answer couldn't be read.


            The schedule may have been saved. Read it with [Get Sync
            Policy](/en/api-reference/sources/get-sync-policy) before sending
            another update. A resend with the old `expectedRevision` answers
            `409` if the first call landed.
        '503':
          content:
            application/json:
              examples:
                knowledge_fs_operation_unavailable:
                  summary: knowledge_fs_operation_unavailable
                  value:
                    code: knowledge_fs_operation_unavailable
                    message: Agent Knowledge Base operation is not available.
                    status: 503
                knowledge_fs_operation_unavailable_upstream:
                  summary: knowledge_fs_operation_unavailable (temporary)
                  value:
                    code: knowledge_fs_operation_unavailable
                    failure:
                      action: retry
                      category: dependency
                      code: KNOWLEDGE_FS_UNAVAILABLE
                      message: >-
                        A service required by Agent Knowledge Base is
                        temporarily unavailable.
                      retryPolicy: manual
                      traceId: 5e2a9c17-3b4d-4f60-8a1b-2c3d4e5f6a7b
                    message: >-
                      A service required by Agent Knowledge Base is temporarily
                      unavailable.
                    status: 503
          description: >-
            - `knowledge_fs_operation_unavailable`: the Agent Knowledge Base
            feature is not set up for this workspace, this operation is not
            available on the deployment, or the key's access to this knowledge
            base changed while the request was being authorized.

            - `knowledge_fs_operation_unavailable`: the request can't be served
            right now. Follow `failure.retryPolicy`.
components:
  schemas:
    KnowledgeBaseSyncPolicy:
      properties:
        created_at:
          description: Creation time, ISO 8601.
          type: string
        custom_interval_seconds:
          description: 'Interval in seconds for `mode: custom`. `null` for the other modes.'
          nullable: true
          type: integer
        enabled:
          description: 'Whether scheduled syncs run. Always `false` with `mode: manual`.'
          type: boolean
        expected_source_version:
          description: Source `version` the schedule is bound to.
          type: integer
        id:
          description: Sync policy ID. It stays the same across updates.
          type: string
        knowledge_space_id:
          description: >-
            Internal ID of the knowledge base. Not the knowledge base ID in the
            path.
          type: string
        mode:
          description: >-
            `manual` (no schedule), `interval` (every 24 hours), or `custom`
            (every `custom_interval_seconds`).
          type: string
        next_run_at:
          description: >-
            When the next scheduled sync is due, ISO 8601. `null` when nothing
            is scheduled.
          nullable: true
          type: string
        revision:
          description: >-
            Schedule revision. Send it as `expectedRevision` on [Update Sync
            Policy](/en/api-reference/sources/update-sync-policy). It increases
            on every update and every time a scheduled sync starts.
          type: integer
        source_id:
          description: Source the schedule belongs to.
          type: string
        updated_at:
          description: Last change, ISO 8601. Also moves when a scheduled sync starts.
          type: string
      type: object
  securitySchemes:
    ApiKeyAuth:
      bearerFormat: API_KEY
      description: >-
        Every request authenticates with an API key: `Authorization: Bearer
        {API_KEY}`. App endpoints take an app API key; knowledge endpoints take
        a knowledge base API key ([Get
        Started](/en/api-reference/guides/get-started)).


        Keep keys server-side; never embed them in client code. Requests with a
        missing or invalid key fail with HTTP `401` (`unauthorized`).
      scheme: bearer
      type: http

````

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