Block Tip

Look at anything. Its picture and its name appear in a small card at the top of the screen, clear of the effect icons and under any boss bar that happens to be up.

Blocks and creatures both. A creature is named by its display name, so a villager who has been given one is introduced by it.

The name is the answer. Everything else on the card is one of two things: a mark you can ignore at a glance, or a fact that would otherwise cost you something to not know.

Turning It Off

Command	Effect
/blocktip	Flip it, whichever way it currently is
/blocktip on	On, definitely
/blocktip off	Off, definitely
/blocktip sneak	Only while sneaking, which is already the gesture for paying attention to one block
/blocktip marks	What the glyphs on the card mean, said in chat

Bare toggle first, because that is what someone types when the tips are in the way and they want them gone now. The explicit forms exist so that telling a child "type slash blocktip on" cannot end with it off.

It is on by default and the preference is stored per player, as the list of people who opted out. A feature you have to switch on is a feature for people who already knew about it, which is the opposite of the point here.

The bare toggle gives back whatever you had: turning tips off and on again returns you to sneak mode if that is where you were, rather than quietly costing you the setting.

Upgrading from a version before sneak mode and hidden blocks starts this list empty - the old preferences are stored in a different shape under a different name, and are left alone on disk rather than half-read. Anyone who had turned tips off turns them off once more.

Blocks You Already Know

All of it or none of it is a blunt choice. The player who is tired of being told what stone is still wants to be told what the thing a mod just added is, so the list is per block and per player.

Command	Effect
/blocktip hide	Never name the block you are looking at again
/blocktip hide <block> [<block>...]	The same, for up to five named blocks
/blocktip show	Name the block you are looking at again
/blocktip show <block> [<block>...]	The same, for up to five named blocks
/blocktip show all	Forget the whole list
/blocktip hidden	Read the list back

The no-argument forms are the ones anybody uses: the block that has just told you what it is for the hundredth time is already on your screen, and pointing at it beats typing its id. show works on a hidden block even though nothing is on screen for it, which is the whole reason it has to be a look and not a card.

Stored per player in the world's saved data, as ids rather than blocks, so uninstalling a mod for a week does not quietly empty the list.

Details Worth Knowing

• Names arrive in your own language. The server sends a translation key, not words, so the client says it in whatever language that client is set to. The facts under the name are the server's own words, and a mod's translation key only survives while it is the only fact on the line - two facts joined by a dot are no longer a key anything can look up.
• Blocks with no item still get named. Fire, portals, the top half of a door: those show the name with no picture, which beats a picture of the wrong thing.
• Creatures show their pick item. A spawn egg for a mob, the boat for a boat: whatever middle-click would hand you, which is the picture of the thing by definition. People get a plain head, middle-click having nothing to offer for them.
• Whichever is nearer wins. A cow standing in front of a wall names the cow, the same rule your eyes are using.
• It costs almost nothing. One raycast per player four times a second, and a packet only when the answer changes. Standing still and staring at a wall sends nothing at all.
• Spectators get no card. Looking through walls would name whatever is behind them.
• Reach is six blocks, a little past arm's length, so it answers before you arrive.

What It Says About Vanilla

A handful of facts the game tracks and never shows, chosen because not knowing each one costs you something:

Looking at	It says
Wheat, carrots, potatoes	83% grown
A spawner	Spawns Zombie
A furnace	Smelting, Out of fuel, or Idle
A chest	50% full, comparator 7
Redstone dust	12/15
Waxed copper	Waxed
A note block	harp, F#3
A hive	3 bees, honey 4/5
Farmland	Watered or Dry
Anything alive	20/20 ♥

These are ranked, most specific first, and as many as fit share the line: a furnace is also a container, so a lit furnace with something in it says both, and the machine that knows what it is doing is the one that survives a line with no room left.

The corner

A skull in the card's top-left corner means mobs can appear on top of that block. Since the light rewrite they need block light of exactly zero, which nobody can check by eye: a torch two blocks too far leaves a square that looks lit and spawns creepers all night.

It has a corner to itself rather than a line, because it is the one thing here that is true of half the world. As a line it was the tip you read most and needed least, and it lost every argument with a tip that had something particular to say - a dark chest reported how full it was and never mentioned what could appear on top of it. In the corner it is checkable at a glance, ignorable just as fast, and true at the same time as everything else on the card.

The corner is kept whether or not there is a skull in it. It would otherwise come and go from block to block and drag the name sideways every time.

What To Hold

The end of the name line answers one question: will what is in my hand do? A glyph says the verdict, and a picture says what would be better, and neither appears when the answer is "anything will". /blocktip marks says the same table in chat, for anyone who is in the game rather than in this file.

At the end of the name	Means
Green tick	The drop is safe with what you are holding, or the crop is ripe
Red plus, with a tool	Right kind of tool, not hard enough. The errand is a furnace, not your hotbar
Red cross	Wrong tool, and swinging now loses the block. On a crop, that it is not ready yet
Yellow star, with a tool	Nothing is at stake. That tool would be quicker, or would hand you the block instead of what it breaks into
An enchanted book	This block drops nothing without silk touch
Shears	Shears give you the block itself: the leaves, the cobweb, the grass

Red means swinging costs you something; yellow and green mean it does not. Each meaning has its own glyph as well as its own colour, because red against yellow is the one distinction a good share of players cannot make, and a screenshot in grey makes it for nobody.

Both of those last two are read from the block's own loot table rather than from a list kept here, so they stay right for whatever a data pack retunes or a mod adds. The question asked is "does the block itself come back", never "does silk touch change the drop" - the second is true of stone and of every ore in the game, and answering it would put a book on half the world.

Each kind of block is asked once and remembered until data packs reload.