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

# Attach policy to user

> Attach a policy to a user

<Info>
  Requires the IAM action **`workspace:AttachPolicy`**. See [WORKSPACE permissions](/workspace/permissions) for the full list, what each one covers, and an example policy.
</Info>


## OpenAPI

````yaml /api-reference/specs/workspace.yaml post /v1/users/{user_id}/policies
openapi: 3.0.3
info:
  title: Basaltic Workspace API
  version: 1.0.0
  description: >
    Organization management: organizations, accounts, human users, users-only
    groups, and organization policies. Account IAM identities may receive
    explicitly delegated organization policies through this API. Personal
    authentication remains at the IAM endpoint.


    Organization resources are global and are resolved in the authenticated
    organization. Canonical CRNs are
    crn:workspace:::organization/<organization-uuid>/<type>/<name-or-uuid>.
    Organization policies are separate from account policies; shared system
    policies use crn:workspace:::policy/<name>.
  contact:
    name: Basaltic Support
    email: ping@basaltic.sh
  license:
    name: Proprietary
    url: https://basaltic.sh/terms
servers:
  - url: https://workspace.basaltic.sh
    description: Global API endpoint
security:
  - BearerAuth: []
paths:
  /v1/users/{user_id}/policies:
    post:
      tags:
        - Workspace
      summary: Attach policy to user
      description: Attach a policy to a user
      operationId: attachUserPolicy
      parameters:
        - $ref: '#/components/parameters/IdempotencyKey'
        - $ref: '#/components/parameters/UserId'
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PolicyAttachRequest'
      responses:
        '204':
          $ref: '#/components/responses/NoContent'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          $ref: '#/components/responses/NotFound'
        '409':
          description: Policy is already attached
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '422':
          $ref: '#/components/responses/UnprocessableEntity'
        '500':
          $ref: '#/components/responses/InternalServerError'
      security:
        - BearerAuth: []
components:
  parameters:
    IdempotencyKey:
      name: Idempotency-Key
      in: header
      description: >-
        Optional client-generated key that makes a create replay-safe. Retrying
        a request with the same key returns the original outcome verbatim
        instead of creating a duplicate resource. Reusing a key with a different
        request body is rejected (422); a request whose key is still being
        processed returns 409. Records are honored for 24 hours. Use a UUID or
        similarly unique token.
      required: false
      schema:
        type: string
        maxLength: 255
      example: 550e8400-e29b-41d4-a716-446655440000
    UserId:
      name: user_id
      in: path
      description: User ID
      required: true
      schema:
        type: string
        format: uuid
      example: 550e8400-e29b-41d4-a716-446655440000
  schemas:
    PolicyAttachRequest:
      type: object
      additionalProperties: false
      required:
        - policy
      properties:
        policy:
          $ref: '#/components/schemas/PolicyReference'
    Error:
      type: object
      required:
        - error
      properties:
        error:
          type: object
          required:
            - code
            - message
            - request_id
          properties:
            code:
              type: string
              description: Error code identifying the type of error
              example: INVALID_INPUT
            message:
              type: string
              description: Human-readable error message
              example: Invalid request parameters
            request_id:
              type: string
              format: uuid
              description: Request ID for debugging
              example: 550e8400-e29b-41d4-a716-446655440000
    PolicyReference:
      type: string
      description: >-
        Organization policy UUID, immutable name in the authenticated
        organization, or fully qualified Workspace CRN. Shared system policies
        use crn:workspace:::policy/<name>. Account IAM policies cannot be
        attached through Workspace.
      example: crn:workspace:::policy/ReadOnlyAccess
  responses:
    NoContent:
      description: Request successful, no content returned
    BadRequest:
      description: Invalid request parameters
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              code: INVALID_INPUT
              message: Invalid request parameters
              request_id: 550e8400-e29b-41d4-a716-446655440000
    Unauthorized:
      description: Authentication required or token invalid
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              code: UNAUTHORIZED
              message: Authentication required
              request_id: 550e8400-e29b-41d4-a716-446655440000
    Forbidden:
      description: Insufficient permissions
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              code: ACCESS_DENIED
              message: You don't have permission to perform this action
              request_id: 550e8400-e29b-41d4-a716-446655440000
    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              code: NOT_FOUND
              message: Resource not found
              request_id: 550e8400-e29b-41d4-a716-446655440000
    UnprocessableEntity:
      description: |
        The request is well-formed but cannot be processed as sent. On the
        operations that accept `Idempotency-Key` this is the key-reuse case: the
        key was first seen with a different request payload, so replaying the
        stored outcome would answer a question the caller did not ask.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              code: IDEMPOTENCY_KEY_REUSED
              message: >-
                This Idempotency-Key was already used with a different request
                payload
              request_id: 550e8400-e29b-41d4-a716-446655440000
    InternalServerError:
      description: Internal server error
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error:
              code: INTERNAL_ERROR
              message: An internal error occurred
              request_id: 550e8400-e29b-41d4-a716-446655440000
  securitySchemes:
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: |
        An OAuth 2.0 bearer token, sent as `Authorization: Bearer <token>`.
        This is the recommended way to authenticate.

        Get one by exchanging a service account's access key pair at
        `POST /v1/oauth/token` with `grant_type=client_credentials`. It is the
        standard client-credentials grant, so any OAuth-aware library will
        obtain and refresh it for you.

        ```
        curl -s -u "$KEY_ID:$SECRET" -d grant_type=client_credentials \
          https://iam.basaltic.sh/v1/oauth/token
        ```

        Tokens last an hour by default. The same access key pair is separately
        your AWS SigV4 credential for the S3-compatible object endpoint, which
        speaks nothing else.

````