Message content

Message content

This flow allows you to create your own message in Postman using an editor and can be used by both admin portal and API users.

For API users who do not want to manage your message templates within Postman, click here for more information.

Message parameters (variables)

You can create multiple {{variables}} when typing out your message content. You can then input the values of each {{variable}}when you send the message from the admin portal or via API.

Variables have to fulfil the following in order to be successfully created

• Can only contain lowercase letters, numbers and _

• Must start with a lowercase letter

• If multiple languages are selected, the same variables must be present in all language tabs.

• Characters are within the GSM-7 character set. See section below on unsupported characters for more info.

Additional notes to message content

Unsupported characters

It is recommended to NOT paste message content into Postman from another editor/MS word/Outlook etc., as this may convert characters into unsupported (non-GSM-7) characters. Please type the message content directly into Postman.

Postman message segment calculator

You may make use of Postman's message segment calculator to

• identify unsupported characters within your message content

• identify non GSM characters within your message content

• check the number of message segments

This is what happens if you include unsupported characters in your messages:

1. unsupported characters changes the message encoding and therefore, significantly increases the number of message segments per SMS.

2. besides cost, long messages with multiple segments will jam the send queue, affecting even the campaigns of other agencies besides your own.

3. Reliability of sending messages cannot be guaranteed beyond 7 message segments per SMS, a limitation imposed by telcos. Hence, we advise you to keep your messages below 7 segments.

Blocking unsupported characters at the UI and API layers [English language only]

Messages containing avoidable unsupported characters will be blocked from sending. Please use the message segment calculator to check your message before sending.

Message content containing unsupported characters will be blocked from sending.

1. On the UI:

Campaign templates that contain unsupported characters cannot be created on the UI/Postman admin portal. This blocking has been implemented since June 2024.

1. On the API:

If your message content is created only at the API layer, we will implement blocking on the Postman production environment from 5 May 2025. This blocking will be available on the Postman test environment from 17 February 2025.

Details have been sent to you via email on 7 February 2025, and also available on the policy guide here.

Error message if your message contains unsupported characters at the API layer:

{
	"error": {
		"code": "parameter_invalid",
		"message": "Parameter values cannot contain avoidable expensive characters. Please refer to the guide (https://postman-v2.guides.gov.sg) to learn more.",
		"type": "domain_error",
		"id": "8758298681140894082"
	}
}

Trailing white spaces in variables

Note that the content within your variables should not start nor end with a space, as this will trigger an error where your message will not be created (400 Bad Request).

eg. "Please report to Clinic A ."

In this example, contents in the variable are coloured, and the trailing spaces at the start/end of the variable content are highlighted in blue. The additional spaces will trigger an error where your message will not be created in Postman.

Possible replacements to unsupported characters

Note that this unsupported character list below is not exhaustive. Please use the message segment calculator to check your message for unsupported characters.

Excluded/unsupported Characters	Description	Possible Replacements that Postman supports
|	vertical line and variants	I (uppercase i)
€	euro	EUR
{	left curly bracket and variants	(
}	right curly bracket and variants	)
[	left square bracket	(
]	right square bracket	)
~	tilde and variants	-
\	backslash and variants	'
`	backtick (note that this is not an apostrophe ' . You can find it to the left of the "1" on your keyboard) and variants	"
‘	acute accent and variants	'
“	double prime quotation mark and variants	"
”	reversed double prime quotation mark and variants	"
¬	logical negation	-
«	left-pointing double angle quotation mark	"
»	right-pointing double angle quotation mark	"
❝ or ❛	heavy double/single turned comma quotation mark ornament	"
❞ or ❜	heavy double/single comma quotation mark ornament	"
÷	division sign	/
¼, ½	vulgar fractions and variants	1/4, 1/2 etc.
•	bullet point	-
⊛, ✢, ✣, ✤, ✥, ✺, ❃, ⧆ etc	asterisk and variants	*