> ## Documentation Index > Fetch the complete documentation index at: https://docs.sailresearch.com/llms.txt > Use this file to discover all available pages before exploring further. # Issue an SSH certificate > Signs your SSH public key so you can connect to a Sailbox that has SSH turned on. Save the returned certificate next to your private key as `-cert.pub` and `ssh` presents it automatically. Certificates are short-lived, so ask for a fresh one rather than storing it long term. Turning SSH on inside a Sailbox needs an SDK or the CLI, and only has to happen once per Sailbox. After that, publish port 22 as a `tcp` listener and dial the host and port it returns. See [Networking](/sailboxes-networking) for the full walkthrough. ## OpenAPI ````yaml /sailbox-openapi.json post /ssh/certificate openapi: 3.1.0 info: title: Sail Sailbox API version: '2026-07-26' description: >- Create and operate Sailboxes over HTTP. Sailboxes are fast-booting virtual machines that you can pause, resume, checkpoint, and fork. Three things need an SDK or the CLI: running commands and moving files, turning on SSH, and building an image. Once SSH is on you can use `ssh` and `scp` for the first of those. See the [HTTP API guide](/sailboxes-http-api). servers: - url: https://sailbox-api.sailresearch.com/v1 security: - BearerAuth: [] tags: - name: Apps description: Groups that own Sailboxes. One app per workload. - name: Lifecycle description: >- A Sailbox's whole life: create it, watch it, stop and start it, terminate it. - name: Checkpoints description: Save a Sailbox to start from later, and copy a running one. - name: Networking description: >- Publish ports, serve them on hostnames you own, and identify a Sailbox to other Sailboxes. - name: Volumes description: >- Shared storage that outlives any one Sailbox. Alpha: these endpoints can still change. - name: SSH access description: Certificates for connecting to a Sailbox with `ssh`. - name: Usage description: Resource usage and spend. - name: Identity description: Who your API key belongs to. paths: /ssh/certificate: post: tags: - SSH access summary: Issue an SSH certificate description: >- Signs your SSH public key so you can connect to a Sailbox that has SSH turned on. Save the returned certificate next to your private key as `-cert.pub` and `ssh` presents it automatically. Certificates are short-lived, so ask for a fresh one rather than storing it long term. Turning SSH on inside a Sailbox needs an SDK or the CLI, and only has to happen once per Sailbox. After that, publish port 22 as a `tcp` listener and dial the host and port it returns. See [Networking](/sailboxes-networking) for the full walkthrough. operationId: issueSSHCertificate requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/IssueSSHCertificateRequest' example: public_key: >- ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIO4yn2NJYJ23X+VL6P4UO7AO5G6l3QqJ0ffuLUbnR2BX you@example.com responses: '200': description: The signed certificate. content: application/json: schema: $ref: '#/components/schemas/SSHCertificate' '400': description: >- The request was rejected. See the error message for the offending field. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: memory_gib for size m must be between 8 and 128 type: invalid_request_error param: null code: null '401': description: The API key is missing or invalid. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: Invalid API key type: authentication_error param: null code: invalid_api_key '402': description: >- The organization is out of credits. The error carries a `billing_url` pointing at the page where you add them. Retry once you have. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: >- Your API key has been disabled due to insufficient credits. Visit https://app.sailresearch.com/billing to add credits. type: billing_error param: null code: credits_exhausted billing_url: https://app.sailresearch.com/billing '403': description: The API key is not allowed to perform this operation. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: sailboxes require an organization-scoped API key type: permission_error param: null code: null '413': description: The request body is larger than the 64 KiB this endpoint accepts. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: request body too large type: invalid_request_error param: null code: null '429': description: >- For its first ten minutes a new organization is capped on how many requests it can have in flight at once, and yours is over that cap. The request never started, so retry it unchanged after the delay in the `Retry-After` header. The limit clears as those requests finish. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: >- Too many concurrent requests. Please retry after some of your organization's in-flight requests complete. type: rate_limit_error param: null code: rate_limited headers: Retry-After: $ref: '#/components/headers/RetryAfter' '500': description: Server error. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: failed to fetch sailbox type: server_error param: null code: null '503': description: >- Sail is momentarily unavailable. Retry after the delay in the `Retry-After` header when one is present, and with backoff otherwise. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: message: Authentication service unavailable type: server_error param: null code: null headers: Retry-After: $ref: '#/components/headers/RetryAfter' components: schemas: IssueSSHCertificateRequest: type: object required: - public_key properties: public_key: type: string minLength: 1 pattern: \S description: Your SSH public key, in OpenSSH `authorized_keys` format. examples: - >- ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIO4yn2NJYJ23X+VL6P4UO7AO5G6l3QqJ0ffuLUbnR2BX you@example.com SSHCertificate: type: object properties: certificate: type: string description: >- Short-lived certificate for your key. Save it next to your private key as `-cert.pub` and `ssh` presents it automatically. key_id: type: string description: Identifier recorded in the certificate. required: - certificate - key_id ErrorResponse: type: object required: - error properties: error: $ref: '#/components/schemas/ErrorObject' ErrorObject: type: object required: - message - type - param - code properties: message: type: string description: Human-readable description of what went wrong. type: type: string description: >- Error category: `invalid_request_error`, `authentication_error`, `permission_error`, `billing_error`, `not_found_error`, `conflict_error`, `rate_limit_error`, or `server_error`. param: oneOf: - type: string - type: 'null' description: >- The request field the error refers to, when the error is about one field. code: oneOf: - type: string - type: integer - type: 'null' description: Stable short code for the error, when one applies. billing_url: type: string format: uri description: Page where you add credits. Sent with a 402. additionalProperties: true headers: RetryAfter: description: >- How many seconds to wait before retrying. On a 429 it also means the request never started, so the retry can reuse the same `Idempotency-Key`. schema: type: integer minimum: 0 securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: API Key ````