> ## Documentation Index > Fetch the complete documentation index at: https://docs-pos.solya.app/llms.txt > Use this file to discover all available pages before exploring further. # Pair a device onto a register > Registers a new peripheral against a store's register. This is an ONBOARDING operation performed while someone is physically installing hardware — it records the pairing, it does not connect to the device, so the paired row is bookkeeping until the till itself reports a link. The `id` is caller-supplied and permanent (use a stable slug such as `reg-pilot-1-printer`); 409s when a device already carries it. `status` defaults to `disconnected`, which is correct for a device that is not online yet — do not claim `ready` you have not observed. Do NOT send `lastSeen`: the server stamps it from its own clock and ignores yours. `store` and `register` are free-text display labels; copy the exact strings already used by the other devices on that register so the fleet listing stays groupable. PERMISSION TRAP (see solya-pos#950): the route guard accepts `pos.settings.manage`, but the use-case additionally asserts the kernel `config:manage` permission and NO `pos.settings.*` scope maps to it, so a principal authenticated by scopes alone clears the guard and then 403s inside the use-case. ## OpenAPI ````yaml /openapi.json post /v1/fleet openapi: 3.0.3 info: title: Solya POS API version: 1.0.0 description: >- The Solya POS backend HTTP surface. Every documented operation is agent-ready: it carries an `operationId`, an agent-facing `description`, the `pos.*` scopes it enforces (`x-required-permissions`) and an `x-agent-tier`. Success responses return the payload as raw JSON; failures return the `ErrorResponse` envelope (`{ error: { code, message, statusCode } }`). servers: - url: / description: The backend, relative to its deployed origin. security: [] paths: /v1/fleet: post: tags: - Network summary: Pair a device onto a register description: >- Registers a new peripheral against a store's register. This is an ONBOARDING operation performed while someone is physically installing hardware — it records the pairing, it does not connect to the device, so the paired row is bookkeeping until the till itself reports a link. The `id` is caller-supplied and permanent (use a stable slug such as `reg-pilot-1-printer`); 409s when a device already carries it. `status` defaults to `disconnected`, which is correct for a device that is not online yet — do not claim `ready` you have not observed. Do NOT send `lastSeen`: the server stamps it from its own clock and ignores yours. `store` and `register` are free-text display labels; copy the exact strings already used by the other devices on that register so the fleet listing stays groupable. PERMISSION TRAP (see solya-pos#950): the route guard accepts `pos.settings.manage`, but the use-case additionally asserts the kernel `config:manage` permission and NO `pos.settings.*` scope maps to it, so a principal authenticated by scopes alone clears the guard and then 403s inside the use-case. operationId: pairFleetDevice requestBody: required: true content: application/json: schema: type: object properties: id: type: string minLength: 1 label: type: string minLength: 1 kind: type: string minLength: 1 store: type: string minLength: 1 register: type: string minLength: 1 status: default: disconnected type: string minLength: 1 required: - id - label - kind - store - register example: id: reg-pilot-1-printer label: Imprimante ticket kind: printer store: Paris Rivoli register: Caisse 1 status: disconnected responses: '201': description: The paired device, with the server-stamped `lastSeen`. content: application/json: schema: type: object properties: id: type: string minLength: 1 label: type: string minLength: 1 kind: type: string minLength: 1 store: type: string minLength: 1 register: type: string minLength: 1 status: type: string minLength: 1 lastSeen: type: string format: date-time pattern: >- ^(?:(?:\d\d[2468][048]|\d\d[13579][26]|\d\d0[48]|[02468][048]00|[13579][26]00)-02-29|\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\d|30)|(?:02)-(?:0[1-9]|1\d|2[0-8])))T(?:(?:[01]\d|2[0-3]):[0-5]\d(?::[0-5]\d(?:\.\d+)?)?(?:Z))$ required: - id - label - kind - store - register - status - lastSeen additionalProperties: false description: The paired device, with the server-stamped `lastSeen`. example: id: reg-pilot-1-printer label: Imprimante ticket kind: printer store: Paris Rivoli register: Caisse 1 status: disconnected lastSeen: '2026-07-13T09:00:00.000Z' '400': description: >- The request failed schema validation; `error.fieldErrors` lists the fields. content: application/json: schema: $ref: '#/components/schemas/ValidationErrorResponse' '401': description: No valid credential was presented — send a bearer token. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '403': description: The actor is authenticated but lacks the required `pos.*` scope. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '409': description: >- The request conflicts with current state (duplicate id or stale version). content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '500': description: An unexpected server error — safe to retry idempotent requests. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' security: - bearerAuth: [] components: schemas: ValidationErrorResponse: type: object required: - error additionalProperties: false description: >- A `VALIDATION_FAILED` envelope carrying the offending fields in `fieldErrors`. properties: error: type: object required: - code - message - statusCode additionalProperties: false properties: code: type: string enum: - VALIDATION_FAILED message: type: string statusCode: type: integer fieldErrors: type: array description: >- One entry per rejected field: the field path and why it was rejected. items: type: object required: - field - message additionalProperties: false properties: field: type: string description: Dot-path of the offending field. message: type: string description: Why the field was rejected. ErrorResponse: type: object required: - error additionalProperties: false description: The uniform failure envelope every non-2xx response returns. properties: error: type: object required: - code - message - statusCode additionalProperties: false properties: code: type: string enum: - VALIDATION_FAILED - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - CONFLICT - BUSINESS_RULE_VIOLATION - INTERNAL_ERROR description: >- Machine-readable kernel `ResultCode` — branch on this, not on `message`. message: type: string description: >- Human-readable explanation. Safe to surface; never leaks server internals. statusCode: type: integer description: >- The HTTP status, mirrored into the body so a client need not read headers. securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT description: >- `Authorization: Bearer `. Accepts EITHER a Keycloak access token (scopes-in-token) OR an opaque POS session token; both resolve to the same `pos.*` scope vocabulary the route guards enforce. ````