Files

List files

GET/api/v1/files

GET /files

curl -X GET 'https://www.unitpost.com/api/v1/files' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0'

Response · 200

{
  "object": "list",
  "has_more": false,
  "data": [
    {
      "object": "file",
      "id": "id_123",
      "purpose": "sms_opt_in_evidence",
      "status": "awaiting_upload",
      "filename": "string",
      "content_type": "string",
      "size_bytes": 1,
      "sha256": "string",
      "failure_reason": "string",
      "upload": {
        "url": "https://example.com",
        "method": "PUT",
        "headers": {},
        "expires_at": "2026-01-01T00:00:00.000Z"
      },
      "created_at": "2026-01-01T00:00:00.000Z",
      "expires_at": "2026-01-01T00:00:00.000Z"
    }
  ]
}

The workspace's unexpired files, newest first, of the purposes this credential may use (sms:manage: the SMS purposes; templates:write or branding:write: image). purpose narrows it. Requires the sms:manage or templates:write or branding:write capability.

Parameters4 fields

Field	Type	Description
`limit`	integer · query	Max rows to return (default 20, max 100).
`after`	string · query	Return rows after this id (forward paging).
`before`	string · query	Return rows before this id (backward paging).
`purpose`	string · query	Only files of this purpose.

Response · 200 fields12 fields

Field	Type	Description
`object`required	string	—
`id`required	string	—
`purpose`required	enumsms_opt_in_evidence \| sms_document \| image	What the file is for: `sms_opt_in_evidence` (PNG, up to 400 KB), `sms_document` (PDF, PNG or JPEG, up to 3 MB), `image` (PNG, JPEG, GIF or WebP, up to 5 MB).
`status`required	enumawaiting_upload \| ready \| failed	`ready`: checked and usable by `file_id`. `awaiting_upload`: an upload session whose bytes haven't been PUT yet (reading the file checks again). `failed`: the uploaded bytes were refused (`failure_reason` says why).
`filename`required	string	—
`content_type`required	string	The type the file's bytes carry (checked by their contents), or, before an upload session's bytes arrive, the type declared.
`size_bytes`required	integer	—
`sha256`required	string \| null	The hex SHA-256 of the bytes once `ready`.
`failure_reason`required	string \| null	—
`upload`required	object \| null	An upload session's PUT, in the create response only (null otherwise).
`created_at`required	string	—
`expires_at`required	string	The file is deleted at this time, 24 hours after it was created, whether or not it was used. An operation that used it keeps its own copy.

200401403422

Create a file

POST/api/v1/files

POST /files

curl -X POST 'https://www.unitpost.com/api/v1/files' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0' \
  -H 'Content-Type: application/json' \
  -d '{ }'

Response · 201

{
  "object": "file",
  "id": "id_123",
  "purpose": "sms_opt_in_evidence",
  "status": "awaiting_upload",
  "filename": "string",
  "content_type": "string",
  "size_bytes": 1,
  "sha256": "string",
  "failure_reason": "string",
  "upload": {
    "url": "https://example.com",
    "method": "PUT",
    "headers": {},
    "expires_at": "2026-01-01T00:00:00.000Z"
  },
  "created_at": "2026-01-01T00:00:00.000Z",
  "expires_at": "2026-01-01T00:00:00.000Z"
}

Hand the API a file for one purpose, then pass its id as file_id (or the field an operation names) to what uses it: a brand document, a toll-free number's opt-in evidence, a 10DLC campaign's screenshot, a library image, the logo. Three ways in, one per call: a public https url (fetched once, no redirects, no private addresses); base64 data with content_type (small files: a request over ~6 MB is refused); or an upload session, for a local file: send content_type and size_bytes without url or data, then PUT the bytes to upload.url with upload.headers within 15 minutes (curl -T file -H "Content-Type: image/png" "<upload.url>"). The bytes are checked by their contents against the purpose (sms_opt_in_evidence: PNG up to 400 KB; sms_document: PDF, PNG or JPEG up to 3 MB; image: PNG, JPEG, GIF or WebP up to 5 MB), never by the label. Files are private, never served back, and expire 24 hours after they're made: what uses one keeps its own copy. Send an Idempotency-Key so a retry makes one file. Requires the sms:manage or templates:write or branding:write capability.

Parameters1 field

Field	Type	Description
`Idempotency-Key`	string · header	Any unique string (1–256 characters, e.g. a UUID). Retrying with the same key and the same body within 24 hours returns the first result instead of sending again; the same key with a different body is `409 invalid_idempotent_request`, and one still in flight is `409 concurrent_idempotent_requests`.

Request body6 fields

Field	Type	Description
`purpose`required	enumsms_opt_in_evidence \| sms_document \| image	What the file is for, which sets what it may be: `sms_opt_in_evidence` (PNG, up to 400 KB), `sms_document` (PDF, PNG or JPEG, up to 3 MB), `image` (PNG, JPEG, GIF or WebP, up to 5 MB). The bytes decide the type, never the name or the label.
`url`	string	A public https address to fetch the file from (no redirects, no private addresses, 12 seconds). One of `url`, `data`, or neither (an upload session).
`data`	string	The bytes, base64 (no `data:` prefix), with `content_type`. A request over ~6 MB is refused before it arrives, so this fits about 4 MB; agents should prefer `url` or an upload session for anything but small files.
`content_type`	enumimage/png \| application/pdf \| image/jpeg \| image/gif \| image/webp	Required with `data` and for an upload session (it is signed into the PUT); refused with `url`.
`size_bytes`	integer	An upload session only: the exact size of the file you'll PUT, in bytes (signed into the PUT). Within the purpose's maximum.
`filename`	string	A name for the file (shown on what uses it). Defaults to the URL's last path part, or `file.<ext>`.

Response · 201 fields12 fields

Field	Type	Description
`object`required	string	—
`id`required	string	—
`purpose`required	enumsms_opt_in_evidence \| sms_document \| image	What the file is for: `sms_opt_in_evidence` (PNG, up to 400 KB), `sms_document` (PDF, PNG or JPEG, up to 3 MB), `image` (PNG, JPEG, GIF or WebP, up to 5 MB).
`status`required	enumawaiting_upload \| ready \| failed	`ready`: checked and usable by `file_id`. `awaiting_upload`: an upload session whose bytes haven't been PUT yet (reading the file checks again). `failed`: the uploaded bytes were refused (`failure_reason` says why).
`filename`required	string	—
`content_type`required	string	The type the file's bytes carry (checked by their contents), or, before an upload session's bytes arrive, the type declared.
`size_bytes`required	integer	—
`sha256`required	string \| null	The hex SHA-256 of the bytes once `ready`.
`failure_reason`required	string \| null	—
`upload`required	object \| null	An upload session's PUT, in the create response only (null otherwise).
`created_at`required	string	—
`expires_at`required	string	The file is deleted at this time, 24 hours after it was created, whether or not it was used. An operation that used it keeps its own copy.

201400401403404409413415422429503

Retrieve a file

GET/api/v1/files/{id}

GET /files/{id}

curl -X GET 'https://www.unitpost.com/api/v1/files/123' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0'

Response · 200

{
  "object": "file",
  "id": "id_123",
  "purpose": "sms_opt_in_evidence",
  "status": "awaiting_upload",
  "filename": "string",
  "content_type": "string",
  "size_bytes": 1,
  "sha256": "string",
  "failure_reason": "string",
  "upload": {
    "url": "https://example.com",
    "method": "PUT",
    "headers": {},
    "expires_at": "2026-01-01T00:00:00.000Z"
  },
  "created_at": "2026-01-01T00:00:00.000Z",
  "expires_at": "2026-01-01T00:00:00.000Z"
}

One file's metadata (the bytes are never served back). For an upload session this checks whether the bytes arrived and pass the purpose's checks: ready, failed (failure_reason), or still awaiting_upload. Requires the sms:manage or templates:write or branding:write capability.

Parameters1 field

Field	Type	Description
`id`required	string · path	—

Response · 200 fields12 fields

Field	Type	Description
`object`required	string	—
`id`required	string	—
`purpose`required	enumsms_opt_in_evidence \| sms_document \| image	What the file is for: `sms_opt_in_evidence` (PNG, up to 400 KB), `sms_document` (PDF, PNG or JPEG, up to 3 MB), `image` (PNG, JPEG, GIF or WebP, up to 5 MB).
`status`required	enumawaiting_upload \| ready \| failed	`ready`: checked and usable by `file_id`. `awaiting_upload`: an upload session whose bytes haven't been PUT yet (reading the file checks again). `failed`: the uploaded bytes were refused (`failure_reason` says why).
`filename`required	string	—
`content_type`required	string	The type the file's bytes carry (checked by their contents), or, before an upload session's bytes arrive, the type declared.
`size_bytes`required	integer	—
`sha256`required	string \| null	The hex SHA-256 of the bytes once `ready`.
`failure_reason`required	string \| null	—
`upload`required	object \| null	An upload session's PUT, in the create response only (null otherwise).
`created_at`required	string	—
`expires_at`required	string	The file is deleted at this time, 24 hours after it was created, whether or not it was used. An operation that used it keeps its own copy.

200401403404422

Delete a file

DELETE/api/v1/files/{id}

DELETE /files/{id}

curl -X DELETE 'https://www.unitpost.com/api/v1/files/123' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0'

Delete a file and its bytes before its 24 hours are up. What already used it keeps its copy. Requires the sms:manage or templates:write or branding:write capability.

Parameters1 field

Field	Type	Description
`id`required	string · path	—

204401403404422

Files

List files

Create a file

Retrieve a file

Delete a file

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