# MSG-009 — HELP reply must be 20–255 characters

> The HELP response must be at least 20 and at most 255 characters.

- **Rule ID:** MSG-009
- **Layer:** Message content (`MESSAGE_CONTENT`)
- **Checks:** `campaign.help_message`
- **Severity:** BLOCKING — Breaking this rule gets the submission rejected outright.
- **When it bites:** Gates approval — get this wrong and registration is refused
- **How it is detected:** Deterministic (settled in code from the submitted values)
- **Fix type:** Fix the field — a better value in the form clears it
- **Required by:** TCR, Twilio, Bird, Sinch
- **Applies:** Applies to every 10DLC registration.
- **Canonical URL:** https://ekas.io/rules/10dlc/message-content/msg-009/

## Why this rule exists

Below 20 characters the reply cannot carry the brand name and a contact route, which are the two things it exists to deliver. Above 255 it exceeds the portable ceiling and is truncated at some providers — losing the tail, which is usually where the opt-out instruction sits.

## How to fix it

Fit the HELP reply into 255 characters carrying the brand name, a real support contact, the rates notice and the opt-out instruction. Drop marketing language before dropping any of those.

## Example of a compliant value

```text
Acme Coffee: for help email support@acmecoffee.com or call 415-555-0134. Msg & data rates may apply. Reply STOP to unsubscribe.
```