> ## Documentation Index > Fetch the complete documentation index at: https://docs.closient.com/llms.txt > Use this file to discover all available pages before exploring further. # TRMNL device log > Accept a diagnostic log payload from a TRMNL device. Firmware posts these on error or warning conditions (low battery, image decode failures, etc.) — Closient persists the payload verbatim because TRMNL's schema is informally specified and may evolve. The staff admin surface renders the JSON for operator triage. **Auth:** ``Access-Token`` header. * ``200`` — payload accepted. * ``401`` — missing, unknown, or disabled ``Access-Token``. ## OpenAPI ````yaml /openapi/openapi-byos.json post /byos/api/log/ openapi: 3.1.0 info: title: BYOS API version: 1.0.0 description: > Closient's TRMNL-compatible **Bring Your Own Server** endpoints. Powers e-ink analytics displays — devices poll ``/api/setup/`` on first boot, then ``/api/display`` on a schedule to fetch the image they should paint. The wire protocol matches TRMNL's BYOS contract verbatim so off-the-shelf reTerminal firmware works without modification. ## Authentication All endpoints require an API key passed via the `X-API-Key` HTTP header, unless otherwise noted. ``` X-API-Key: csb__ ``` Generate API keys in **Settings > API Keys** in your dashboard, or via the Account API. Session-based (cookie) authentication is also accepted for browser-based access. ## Rate Limits | Tier | Requests / minute | Requests / day | |-------------|-------------------|----------------| | Default | 300 | 10,000 | | Custom | Contact us | Contact us | Rate-limit headers are included on every response so callers can self-throttle without hitting our 429s ("informed governor"): - `RateLimit-Policy` — every active window, e.g. `300;w=60, 10000;w=86400` - `RateLimit-Limit` — quota for the **most-restrictive** currently-active window - `RateLimit-Remaining` — requests left in that window - `RateLimit-Reset` — seconds until that window resets (relative; clock-skew safe) Legacy `X-RateLimit-*` aliases are also emitted for back-compat. `X-RateLimit-Reset` keeps the absolute Unix-timestamp shape to avoid breaking existing consumers. When rate-limited, you receive `429 Too Many Requests` with a `retry_after_seconds` field in the error envelope and a `Retry-After` header. ## Pagination List endpoints return paginated results in this envelope: ```json { "data": [...], "pagination": { "page": 1, "page_size": 25, "total_count": 342, "total_pages": 14, "has_next": true, "has_previous": false } } ``` Use `?page=2&page_size=50` query parameters. Maximum page size is 100. ## Error Responses All errors conform to [RFC 9457 Problem Details](https://www.rfc-editor.org/rfc/rfc9457) with `Content-Type: application/problem+json`: ```json { "type": "https://closient.com/docs/errors/not_found", "title": "Not Found", "status": 404, "detail": "The requested resource was not found.", "error_code": "not_found", "retryable": false, "timestamp": "2026-03-31T12:00:00+00:00" } ``` Common error codes: `unauthorized` (401), `forbidden` (403), `not_found` (404), `validation_error` (422), `rate_limited` (429), `internal_error` (500). termsOfService: https://www.closient.com/terms/ servers: - url: https://www.closient.com security: [] externalDocs: description: Closient Documentation url: https://docs.closient.com paths: /byos/api/log/: post: tags: - byos-trmnl summary: TRMNL device log description: >- Accept a diagnostic log payload from a TRMNL device. Firmware posts these on error or warning conditions (low battery, image decode failures, etc.) — Closient persists the payload verbatim because TRMNL's schema is informally specified and may evolve. The staff admin surface renders the JSON for operator triage. **Auth:** ``Access-Token`` header. * ``200`` — payload accepted. * ``401`` — missing, unknown, or disabled ``Access-Token``. operationId: apps_boards_api_trmnl_trmnl_log parameters: [] requestBody: content: application/json: schema: $ref: '#/components/schemas/LogIn' required: true responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/LogAcceptedOut' '400': description: Bad Request content: application/problem+json: schema: $ref: '#/components/schemas/ErrorOut' '401': description: Unauthorized content: application/problem+json: schema: additionalProperties: true title: Response type: object '403': description: Forbidden content: application/problem+json: schema: $ref: '#/components/schemas/ErrorOut' '404': description: Not Found content: application/problem+json: schema: $ref: '#/components/schemas/ErrorOut' '405': description: Method Not Allowed content: application/problem+json: schema: $ref: '#/components/schemas/ErrorOut' '422': description: Unprocessable Content content: application/problem+json: schema: $ref: '#/components/schemas/ErrorOut' '429': description: Too Many Requests content: application/problem+json: schema: $ref: '#/components/schemas/ErrorOut' security: - TRMNLDeviceAuth: [] components: schemas: LogIn: description: |- Payload for ``POST /api/log/``. TRMNL firmware posts ``{log: {...}}``. The ``log`` body's schema is owned by TRMNL and is not formally specified — Closient persists it verbatim for diagnosis. examples: - log: battery_voltage: 3.41 level: warn message: Low battery — 3.41V uptime_seconds: 86400 properties: log: additionalProperties: true description: >- Free-form JSON object posted by TRMNL firmware. Persisted verbatim — schema is owned by firmware. title: Log type: object title: LogIn type: object LogAcceptedOut: description: Empty-ish ACK returned from ``POST /api/log/``. examples: - status: 200 properties: status: default: 200 description: >- Always 200 on accept. Non-2xx is reserved for malformed payloads (rejected upstream by Pydantic). title: Status type: integer title: LogAcceptedOut type: object ErrorOut: title: ErrorOut type: object description: RFC 9457 Problem Details error body. properties: type: type: string format: uri title: type: string status: type: integer detail: type: string error_code: type: string retryable: type: boolean timestamp: type: string format: date-time required: - type - title - status - detail examples: - type: https://closient.com/docs/errors/not_found title: Not Found status: 404 detail: The requested resource was not found. error_code: not_found retryable: false timestamp: '2026-03-31T12:00:00+00:00' securitySchemes: TRMNLDeviceAuth: type: apiKey in: header name: Access-Token ````