Email Signatures

ReferenceUpdated June 14, 2026

Email Signatures

Manage the workspace's reusable email signatures. A signature's display name (signature_name) is derived automatically from the first line of signature_text.

Signatures are part of the generation configuration: a saved signature's text is passed as the email_signature option when you preview, generate for one lead, or generate a batch — it's appended to the generated emails.

Reads require the signatures:read scope; writes require signatures:write. All operations are scoped to the API key's workspace.

List signatures

GET /api/v1/signatures · scope signatures:read

Query parameters

Parameter	Type	Required	Description
`limit`	number	No	Max results (default 50, max 100).
`offset`	number	No	Pagination offset (default 0).

Example request

curl -X GET "https://app.machfive.io/api/v1/signatures?limit=20" \
  -H "Authorization: Bearer YOUR_API_KEY"

Response (200 OK)

{
  "data": [
    {
      "id": "uuid",
      "signature_text": "Jane Doe\nVP Marketing, Acme Inc\njane@acme.com",
      "signature_name": "Jane Doe",
      "created_by": "user-uuid",
      "created_at": "2025-01-15T12:00:00.000Z",
      "updated_at": "2025-01-15T12:00:00.000Z"
    }
  ],
  "has_more": false,
  "total": 1
}

Field	Type	Description
`data[].id`	string (UUID)	Signature ID.
`data[].signature_text`	string	Full signature text.
`data[].signature_name`	string \| null	Auto-derived from the first line.
`data[].created_by`	string \| null	User who created it (workspace owner for API-created signatures).
`data[].created_at` / `updated_at`	string \| null	Timestamps (ISO 8601).

Error responses

Status	Error	Description
401	UNAUTHORIZED	Missing or invalid API key.
403	FORBIDDEN	Key missing the `signatures:read` scope.
429	RATE_LIMITED	Per-key rate limit exceeded; honor `Retry-After`.
500	INTERNAL_ERROR	Server error.

Create a signature

POST /api/v1/signatures · scope signatures:write

signature_name is set server-side from the first line of the text.

Request body

Field	Type	Required	Description
`signature_text`	string	Yes	The signature content (1–5000 characters, trimmed).

Example request

curl -X POST "https://app.machfive.io/api/v1/signatures" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "signature_text": "Jane Doe\nVP Marketing, Acme Inc\njane@acme.com" }'

Response (201 Created)

{
  "id": "uuid",
  "signature_text": "Jane Doe\nVP Marketing, Acme Inc\njane@acme.com",
  "signature_name": "Jane Doe",
  "created_by": "user-uuid",
  "created_at": "2025-01-15T12:00:00.000Z",
  "updated_at": "2025-01-15T12:00:00.000Z"
}

Error responses

Status	Error	Description
400	BAD_REQUEST	Missing or invalid `signature_text`.
401	UNAUTHORIZED	Missing or invalid API key.
403	FORBIDDEN	Key missing the `signatures:write` scope.
429	RATE_LIMITED	Per-key rate limit exceeded; honor `Retry-After`.
500	INTERNAL_ERROR	Server error.

Update a signature

PUT /api/v1/signatures/:id · scope signatures:write

Replaces the signature text and re-derives signature_name.

Path parameters

Parameter	Type	Description
`id`	string (UUID)	Signature ID.

Request body

Field	Type	Required	Description
`signature_text`	string	Yes	New signature content (1–5000 characters, trimmed).

Example request

curl -X PUT "https://app.machfive.io/api/v1/signatures/SIGNATURE_ID" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "signature_text": "Jane Doe\nHead of Growth, Acme Inc\njane@acme.com" }'

Response (200 OK)

{
  "id": "uuid",
  "signature_text": "Jane Doe\nHead of Growth, Acme Inc\njane@acme.com",
  "signature_name": "Jane Doe",
  "created_by": "user-uuid",
  "created_at": "2025-01-15T12:00:00.000Z",
  "updated_at": "2025-01-16T09:00:00.000Z"
}

Error responses

Status	Error	Description
400	BAD_REQUEST	Missing or invalid `signature_text`.
401	UNAUTHORIZED	Missing or invalid API key.
403	FORBIDDEN	Key missing the `signatures:write` scope.
404	NOT_FOUND	Signature not found or not in this workspace.
429	RATE_LIMITED	Per-key rate limit exceeded; honor `Retry-After`.
500	INTERNAL_ERROR	Server error.

Delete a signature

DELETE /api/v1/signatures/:id · scope signatures:write

Path parameters

Parameter	Type	Description
`id`	string (UUID)	Signature ID.

Example request

curl -X DELETE "https://app.machfive.io/api/v1/signatures/SIGNATURE_ID" \
  -H "Authorization: Bearer YOUR_API_KEY"

Response (200 OK)

{ "id": "uuid", "deleted": true }

Error responses

Status	Error	Description
401	UNAUTHORIZED	Missing or invalid API key.
403	FORBIDDEN	Key missing the `signatures:write` scope.
404	NOT_FOUND	Signature not found or not in this workspace.
429	RATE_LIMITED	Per-key rate limit exceeded; honor `Retry-After`.
500	INTERNAL_ERROR	Server error.

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