Perceiving readied actions

[Tanarii]

As a DM, do you allow characters (either PCs/allies or their enemies) to perceive an action has been readied? Do you allow them to know exactly what action has been readied, and/or what will trigger it?

As a player, what are your expectations when you declare a ready action, in terms of the enemy knowing that you've readied an action, knowing what the trigger is, and knowing what the action is? As a player, what are your expectations for those three things when an enemy readies an action?

I had a player get upset in this morning's session because an enemy acted based on their out loud declaration of the PC taking a Ready Action, and the specific trigger and action. I told them I declare the enemy triggers and actions out loud too so they also have that knowledge to make decisions on. And that's how I run my game, known info is generally known in universe and can be acted on. Basically he grumbled, I grumbled, we all grumbled, and we moved on with the game. They all know my stance: it's only metagaming if we try to pretend we don't have knowledge we have, and doing that usually gives the DM an unfair advantage.

But as usual, when I come across an interesting ruling I had to make in game, I like to share and get other people's points of view. So go to it!

[Dork_Forge]

Spellcasting is clear cut for me, if you could see them cast the spell any other time you can see them cast it to ready it. Other things I would maybe be a little more vague on like declare an enemy has taken a 'readied stance' just so the readied action doesn't come out of the blue to them. If they have a good passive perception/investigation and are a martial then I'd say something like "x, you recognise that they're preparing to thrust their spear at anyone that comes close."

[JackPhoenix]

Depends on action. Readying a spell is obvious, as it involves casting the spell in the first place and then waiting to release it. Same with most ranged attacks... you have your weapon loaded and aimed at the general direction of where you want to shoot.

Readying to pull a lever when someone moves to certain spot could go both ways, depending on description of the character's action... is the character waiting with his hand on the lever? Is he just standing next to it?

Readying to run away if someone moves next to the character is unnoticeable... sure, others will notice the character didn't attack or whatever, but they won't know why.

Exact trigger is pretty much always unknown. Others may know the character is waiting for something to finish the spell or the general direction of the aimed ranged weapon, but they have no way of knowing if they are aiming at first enemy who shows up, waiting for specific target, waiting for certain number of enemies gathered together for AoE, or whatever. Of course, if the lone would-be victim is aware of the trapdoor the lever controls and sees the character waiting with a hand on the lever, it doesn't take a genius to realize what's about to happen if he steps on the door.

[Trandir]

I am a player and I expect that I can't tell if someone is reading an action to attack, dash or similar things that have no particular indicator or telling sign as well as my enemies.

If someone prepares to cast spell with either somatic or verbal components it's resonable to assume that you know that's gonna happen but not what spell nor where it will strike. How could I know where a wizard is going to throw a fireball or if he instead is preparing a fog cloud to cover his retreat and tricking an opponent into keeping the distance?
If the spell has no somatic or verbal components (sorcerer metamagic or warcaster) you shouldn't be able to distinquish the preparing a cast from being in combat stance.

If you are preparing to use a magic item or throw something everyone with a little passive perception should be able to notice it.

Reading an action to attack with ranged weapons should also be fairly obvious.

[Tanarii]

Spells are a special case in that they're clearly defined how they work. Creatures only know the effects of a spell if they are perceivable. And you can't even then, you can't indentify the specific spell cast without a reaction and a Arcana check. Or you can cast an Identify spell to detect an otherwise Un-perceivable ongoing effect when a spell has been cast.

I concede there might be some declared actions and triggers which are difficult to define as perceivable in-universe. But any attack or movement and almost all other standard combat actions, and any trigger for an attack I'm going to allow to be declared, can conceivably be visible in game. Including "I move away if X gets close" or the like.

[Lunali]

I'd rule that most readied actions are obvious, though the triggers won't always be.