Does the reply to the Message cantrip have a time/distance limit?

Question

The message cantrip says the following:

You point your finger toward a creature within range and whisper a message. The target (and only the target) hears the message and can reply in a whisper that only you can hear.

The spell itself has a duration of 1 round and a range of 120 feet, but I assume this is for the caster's "outgoing" message. Is there a time limit or a distance limit on the recipient's reply?

I ask this because a player claims that the recipient of the message can reply any time in the future at any distance, because the spell does not specify that, and they have therefore used the message cantrip as a way to have an NPC tell them when someone is ready to collect (i.e. casting message on the NPC, with the message being "reply to this message spell when you're done").

I believe that the intent is that the recipient is expected to reply straight away, but that isn't specified. For contrast, the sending spell (which also has a duration of 1 round) does specify when the recipient is allowed to respond:

You send a short message of twenty-five words or less to a creature with which you are familiar. The creature hears the message in its mind, recognizes you as the sender if it knows you, and can answer in a like manner immediately.

Sending says that the recipient must reply immediately, whereas message does not specify when the recipient must reply, hence my player claiming that there is no time limit.

Regarding the distance thing, this is also treading on the toes of the sending spell somewhat, except that the caster of message still has to be within 120 feet of the recipient (it's only the recipient that seems to have no limit on distance), whereas sending allows the caster to be the one to initiate long-distance communication.

Is my player correct? Can the recipient of a message really reply after any length of time after they receive the message, and over any distance?

Answer 1

There's a time limit, but no distance limit

Time

You have 1 round to use the Message. Although most uses occur on your turn immediately after you cast it, you can wait until you move (see below) or even wait until somebody else's turn to send the message.

Similarly, the recipient can wait until later in the round to reply. However, they have two limitations:

1. They can't reply until after you have sent your message, and
2. They must reply within the 1 round duration of the spell.

Distance

From the Range section of the spellcasting rules (emphasis mine):

The target of a spell must be within the spell's range. [...] Once a spell is cast, its effects aren't limited by its range, unless the spell's description says otherwise.

Your target must be within 120 feet when you cast the spell. However, you don't have to use the spell immediately - you have 1 round. If the distance between you and the target increases, by walking or teleporting or even if one of you goes to another plane, "its effects aren't limited by its range, unless the spell's description says otherwise." Message does not "say otherwise" so there is no distance limitation.

Answer 2

You already answered your own question: 6 seconds (1 round) and 120 feet.

The Range section of the spellcasting rules says (emphasis mine):

The target of a spell must be within the spell's range. [...] Once a spell is cast, its effects aren't limited by its range, unless the spell's description says otherwise.

and the Duration section says (emphasis mine):

A spell's duration is the length of time the spell persists. A duration can be expressed in rounds, minutes, hours, or even years. Some spells specify that their effects last until the spells are dispelled or destroyed.

So we'll look at the easy one first. The duration of Message is "1 round". Once that round is up, the magic stops and the communication link is severed. There can be no reply. Of course, DMs can extend this to fit the narrative, but generally it should be an immediate reply.

Range is a little trickier, as the general description says the target must be within range. However it ends with, "its effects aren't limited by its range". This does not mean that the target can be at the edge of 120 feet and start walking away and still be considered "in range". It means that if you cast a Fireball which has a range of 150 feet, the 20-foot radius can extend past that point. So you can effectively hit a creature 170 feet away - but the point of origin must be within 150 feet.

Answer 3

Let's break it down:

• What does the spell allow you to do? It allows you to send and receive a message.
• What are the restrictions of this? Duration (1 round), and distance (120 feet).

So this means that a two way conversation happens within this distance and time frame. The duration in this instance is to specify that when you take your turn to send the message, the reply happens on their turn, within that one round. If they don't reply, the spell ends at the beginning of your next turn.

Generally for RAW, the rule of thumb in 5e is that all the information is specified within the description. If it doesn't specify something, then that isn't the case. For example, if it allows for the reply to be at any time or at any distance, it would say so.