SmallStep

SmallStep Authentication API

Create API tokens

Documentation GitHub OpenAPI

Operations 1

POST /auth Authenticate #

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OpenAPI Specification

openapi: 3.2.0
info:
  contact:
    email: support@smallstep.com
    name: Smallstep Support
    url: https://support.smallstep.com
  description: '# Getting Started

    First you''ll need to get an API token from the Team Settings page of your [Smallstep dashboard](https://smallstep.com/app).


    Then you can try [listing certificates](/operations/list-certificates) for your first API call:

    ```

    set +o history

    echo "Authorization: Bearer [your API token]" > api_headers

    set -o history

    curl -H @api_headers https://gateway.smallstep.com/api/certificates

    ```


    More resources:

    * [Terraform Provider](https://github.com/smallstep/terraform-provider-smallstep)

    * [Python Client](https://github.com/smallstep/smallstep-python)

    '
  license:
    name: Apache 2.0
    url: https://www.apache.org/licenses/LICENSE-2.0
  summary: Smallstep API
  title: Smallstep Authentication API
  version: '2025-01-01'
servers:
- url: https://gateway.smallstep.com/api
security:
- JWT: []
tags:
- description: Create API tokens
  name: Authentication
paths:
  /auth:
    x-internal: true
    post:
      description: Use client certificate authentication to get an API token
      operationId: PostAuth
      requestBody:
        content:
          application/json:
            schema:
              properties:
                audience:
                  enum:
                  - step-agent
                  type: string
                bundle:
                  items:
                    format: binary
                    type: string
                  type: array
                teamID:
                  type: string
                teamSlug:
                  type: string
              type: object
        description: Client authentication information.
      responses:
        '201':
          content:
            application/json:
              schema:
                properties:
                  token:
                    type: string
                type: object
          description: A new auth token.
        '400':
          $ref: '#/components/responses/400'
        '401':
          $ref: '#/components/responses/401'
        '403':
          $ref: '#/components/responses/403'
        '500':
          $ref: '#/components/responses/500'
      security:
      - mtls: []
      summary: Authenticate
      tags:
      - Authentication
      x-internal: true
components:
  headers:
    X-Smallstep-Api-Version:
      description: API version to use. Will be reflected in responses.
      example: '2025-01-01'
      schema:
        format: date
        type: string
    X-Request-Id:
      description: A request ID provided by the client. If not provided, the server will generate one. Will be reflected in responses.
      example: abcdef
      schema:
        type: string
  responses:
    '500':
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/error'
      description: Internal server error
      headers:
        X-Request-Id:
          $ref: '#/components/headers/X-Request-Id'
        X-Smallstep-Api-Version:
          $ref: '#/components/headers/X-Smallstep-Api-Version'
    '400':
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/error'
      description: Bad request
      headers:
        X-Request-Id:
          $ref: '#/components/headers/X-Request-Id'
        X-Smallstep-Api-Version:
          $ref: '#/components/headers/X-Smallstep-Api-Version'
    '403':
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/error'
      description: Forbidden
      headers:
        X-Request-Id:
          $ref: '#/components/headers/X-Request-Id'
        X-Smallstep-Api-Version:
          $ref: '#/components/headers/X-Smallstep-Api-Version'
    '401':
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/error'
      description: Unauthorized
      headers:
        X-Request-Id:
          $ref: '#/components/headers/X-Request-Id'
        X-Smallstep-Api-Version:
          $ref: '#/components/headers/X-Smallstep-Api-Version'
  schemas:
    error:
      example:
        message: ID must be a valid UUID
      properties:
        message:
          description: A description of the error.
          type: string
      required:
      - message
      title: Error
      type: object
  securitySchemes:
    JWT:
      scheme: bearer
      type: http
    mtls:
      description: Use a client certificate issued by a trusted root to get short-lived bearer tokens with the step CLI.
      type: mutualTLS