salesforce-composite-envelope-builder/composite-envelope-builder/force-app/main/default/classes/DocusignCompositeEnvelopeBuilder.cls

            String envelopeSubject = combinedName;
            // Truncate subject to 100 characters maximum as required by Docusign
            if (envelopeSubject.length() > 100) {
                envelopeSubject = envelopeSubject.left(97) + '...';
            }
            String envelopeBody = bodyParts.isEmpty() ? '' : String.join(bodyParts, '\n\n---\n\n');
            myEnvelope = myEnvelope.withEmail(envelopeSubject, envelopeBody);