Render a template preview

POST /v1/admin/email/templates/{key}/preview

• Operation ID: previewEmailTemplate
• Tags: Email templates
• Base URL: http://localhost:8787

Renders placeholders for a version (default: the published version) using vars, or the template's variables_schema.sample when omitted. Missing variables render empty. Nothing is sent.

Workflow: Integration guide.

Authentication: staff Bearer JWT with permission email.read.

Authentication

• Auth: staff Bearer JWT (Authorization: Bearer <access_token>) with the permissions below.
• Required permissions: email.read

Parameters

Name	In	Type	Required	Description
key	path	string	yes	Pattern: ^[a-z][a-z0-9-]{1,63}$

Request body

Required: yes.

Content type: application/json

Schema: object

Field	Type	Required	Description
version	integer	no	Greater than: 0
vars	object	no	-

Responses

200

Rendered preview.

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (EmailTemplatePreview)

Field	Type	Required	Description
version	integer	yes	-
subject	string	yes	-
html	string	yes	-

Errors

400

Request validation failed.

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (ValidationErrorBody)

Field	Type	Required	Description
success	boolean	yes	One of: false
error	object	yes	-
error.name	string	yes	One of: "ZodError"
error.issues	object[]	yes	-
error.issues[].code	string	yes	-
error.issues[].path	(string | number)[]	yes	-
error.issues[].message	string	yes	-

Request validation

{
  "success": false,
  "error": {
    "name": "ZodError",
    "issues": [
      {
        "code": "custom",
        "path": [
          "field"
        ],
        "message": "Invalid value"
      }
    ]
  }
}

401

Missing, malformed, expired or wrong-audience Bearer token (missing_token, invalid_token, invalid_audience).

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (ErrorBody)

Field	Type	Required	Description
error	string	yes	Stable machine-readable error code, e.g. forbidden, not_found.
details	any	no	Optional structured context. For 403 it is { perm }.

Error response

{
  "error": "missing_token"
}

403

Authenticated but lacking the required permission. details.perm lists the accepted permission keys.

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (ErrorBody), fields as described above.

Error response

{
  "error": "forbidden",
  "details": {
    "perm": "email.read"
  }
}

404

template or version_<n>.

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (ErrorBody), fields as described above.

Error response

{
  "error": "template"
}

422

no_version_to_preview: no version given and none published.

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (ErrorBody), fields as described above.

Error response

{
  "error": "no_version_to_preview"
}

500

Unexpected server error (internal). No details are returned.

• Header x-request-id: Request identifier; quote it when reporting an error. Content type: application/json

Schema: object (ErrorBody), fields as described above.

Error response

{
  "error": "internal"
}

Examples

curl

curl -X POST 'http://localhost:8787/v1/admin/email/templates/example/preview' \
  -H "Authorization: Bearer $ACCESS_TOKEN" \
  -H 'Content-Type: application/json' \
  --data '{"version":1,"vars":{}}'

TypeScript

const accessToken = process.env.ACCESS_TOKEN; // user JWT from your sign-in flow

const response = await fetch("http://localhost:8787/v1/admin/email/templates/example/preview", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${accessToken}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "version": 1,
    "vars": {}
  }),
});
if (!response.ok) throw new Error(`HTTP ${response.status}: ${await response.text()}`);
const data = response.status === 204 || response.status === 205
  ? undefined
  : response.headers.get("content-type")?.includes("json")
    ? await response.json()
    : await response.text();