This is your new text block with the first paragraph.
\",\"attributes\":{\"align\":\"left\",\"padding\":\"15px 15px 15px 15px\",\"line-height\":1.5,\"containerWidth\":600},\"customKey\":null}],\"uid\":\"HJQ8ytZzW\"}],\"layout\":1,\"backgroundColor\":null,\"backgroundImage\":null,\"paddingTop\":0,\"paddingBottom\":0,\"paddingLeft\":0,\"paddingRight\":0,\"uid\":\"Byggju-zb\"}]}],\"style\":{\"h1\":{\"font-family\":\"Helvetica, Arial, sans-serif\",\"font-size\":\"22px\",\"font-weight\":\"bold\"},\"a\":{\"color\":\"#0000EE\"},\"h2\":{\"font-family\":\"Helvetica, Arial, sans-serif\",\"font-size\":\"17px\",\"font-weight\":\"bold\"},\"h3\":{\"font-family\":\"Helvetica, Arial, sans-serif\",\"font-size\":\"13px\",\"font-weight\":\"bold\"},\"p\":{\"font-family\":\"Helvetica, Arial, sans-serif\",\"font-size\":\"11px\"},\"ul\":{\"font-size\":\"11px\",\"font-family\":\"Helvetica, Arial, sans-serif\"},\"li\":{\"font-size\":\"11px\",\"font-family\":\"Helvetica, Arial, sans-serif\"},\"ol\":{\"font-size\":\"11px\",\"font-family\":\"Helvetica, Arial, sans-serif\"},\".rounded>table\":{\"border-collapse\":\"separate\"}},\"fonts\":[\"Helvetica, Arial, sans-serif\"],\"feedBlocksApplyToAll\":{},\"langs\":[{\"key\":\"en\",\"primary\":true,\"translations\":{\"9qJHlWzLp\":{\"content\":\"This is your new text block with the first paragraph.
\"}}}]}" }, "options": { "type": "object", "properties": { "minify": { "type": "boolean", "description": "Whether to minify the output HTML", "example": true }, "fonts": { "type": "string", "description": "JSON string containing an array of font objects with label, style, and url properties", "example": "[{\"label\":\"Open Sans\",\"style\":\"Open Sans, sans-serif\",\"url\":\"https://fonts.googleapis.com/css?family=Open+Sans:400,700\"}]" }, "emailServiceProvider": { "type": "string", "enum": ["mailchimp", "sparkpost"], "description": "Target email service provider", "example": "mailchimp" }, "mergeTags": { "type": "array", "description": "Array of merge tags for template variable substitution", "example": [] }, "evaluateMergeTags": { "type": "boolean", "description": "Whether to evaluate merge tags in the template", "example": false }, "variants": { "type": "object", "properties": { "evaluate": { "type": "boolean", "description": "Whether to evaluate variants", "example": false }, "enrichWithConditions": { "type": "boolean", "description": "Whether to enrich with conditional logic", "example": true } } }, "desktopFirst": { "type": "boolean", "description": "Whether to prioritize desktop layout", "example": false }, "language": { "type": "string", "description": "Template language code", "example": "en" } } }, "syncedSections": { "type": "array", "description": "Resolved content for every synced section referenced by the template. A section in the template JSON that carries a `syncedId` is stored as a lightweight reference only; the rendering pipeline must be supplied with the matching content here, otherwise the section renders empty. Fetch each referenced synced section from your saved-sections storage (see the Saved Blocks and Synced Sections guide) and pass it in this array before calling this endpoint.", "items": { "type": "object", "required": ["id", "definition"], "properties": { "id": { "type": "number", "description": "ID of the synced section. Must match the `syncedId` on a section node in the template JSON.", "example": 1 }, "definition": { "type": "string", "description": "JSON-encoded MJML definition of the synced section (string, not a nested object)." }, "translation": { "type": "string", "description": "Optional JSON-encoded locale-keyed translation map for multilingual templates. Required if the template has language mutations and the section contains translatable content." } } } } } }, "Json2HtmlSuccess": { "type": "object", "required": ["html"], "properties": { "html": { "type": "string", "description": "Rendered HTML output", "example": "Hello World" }, "warnings": { "type": "array", "items": { "$ref": "#/components/schemas/Warning" }, "description": "Optional warnings about the conversion" } } }, "ErrorResponse": { "type": "object", "required": ["message"], "properties": { "message": { "type": "string", "description": "Error message", "example": "An error occurred" } } }, "ValidationErrorResponse": { "type": "object", "required": ["message", "errors"], "properties": { "message": { "type": "string", "description": "Main error message", "example": "Validation failed" }, "errors": { "type": "array", "items": { "type": "object", "properties": { "field": { "type": "string", "description": "Field that failed validation", "example": "definition" }, "message": { "type": "string", "description": "Specific validation error message", "example": "Field is required" } } }, "description": "List of validation errors" } } } } }, "paths": { "/email/v1/json2html": { "post": { "description": "Convert JSON template to HTML using MJML rendering engine. Authentication is done via the X-Secret-Key header.\n\nIf the template contains synced sections (any section node with a `syncedId` property), the matching content must be supplied through the optional `syncedSections` request field. Synced section references are resolved before merge tag evaluation and variant rendering: the endpoint looks up each `syncedId` in the supplied array, splices the section's full MJML into the template, regenerates child block UIDs to avoid collisions, and (for multilingual templates) merges per-locale translations into the template's `langs` array. Without this step, synced sections render as empty placeholders.", "summary": "JSON to HTML", "operationId": "convertJson2Html", "tags": ["Conversion API"], "security": [ { "SecretKeyAuth": [] } ], "requestBody": { "description": "Template conversion request", "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/Json2HtmlRequest" } } } }, "responses": { "200": { "description": "Template converted successfully", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/Json2HtmlSuccess" } } } }, "400": { "description": "Bad request - missing or invalid request body", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ErrorResponse" } } } }, "401": { "description": "Unauthorized - invalid or expired API key", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ErrorResponse" } } } }, "422": { "description": "Validation error - invalid request format", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ValidationErrorResponse" } } } }, "500": { "description": "Internal server error", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/ErrorResponse" } } } } } } } } }