STRING

Two professions want this at once, and they do not want it equally. No recipe in Java 26.2 produces it: it drops from cats, cave spiders, spiders and 1 other, and it comes out of cobweb and tripwire.

The Fisherman takes it early, at novice, but only shows that slot on a coin flip. The Fletcher takes it later, at journeyman, and shows it every single time a villager reaches that tier. One is a maybe, the other is a guarantee, and knowing which is which decides where the string actually ends up going.

The Fisherman at novice pays an emerald per 20 string, and the Fletcher at journeyman does better, an emerald per 14. Between the two, the Fletcher is both the cheaper sale and the sure thing.

The best rate any villager offers is an emerald per 14 string, from the Fletcher, and 1 of the other 4 pays out faster. No villager sells string back, so it is emeralds out and nothing in.

One slot at the Fletcher takes 14 string a trade, 16 trades, 16 emeralds. 8 of the 72 villagers that pay emeralds, emptied out:

16 acacia boats against 512 rotten flesh for the same 16 emeralds, 32 times the carrying, and the shortest wait is the Mason at 10 real minutes of shelf, gathering not counted. String itself pays 14 an emerald, so 42 of the 72 ask less and 28 ask more.

Two villagers, two tiers, one clearly better deal. The Fletcher offer sits at level 3 of five and never rolls away once that tier is reached, which is what makes it the one worth levelling a Fletcher toward on purpose.

Its slot allows 16 sales before it locks, refilling on the same restock schedule every profession shares. Selling a large stockpile in one sitting means working around that limit rather than around any roll.

The Fletcher slot closes after 16 sales, and reopens 2 real minutes later, the standard wait for any profession. A Minecraft day runs 20 real minutes long and fits two of those refills.

Camped for a full day, that Fletcher takes 448 string off your hands for 32 emeralds, and the pace does not change whether you watch the trade happen or walk away and come back later.

Aim string at the Fletcher, not the Fisherman. The Fletcher pays better and never skips the slot, so a villager worth levelling for string is a Fletcher every time, not whichever profession happens to be nearby.

Where the emeralds go back: that same Fletcher sells arrows, 16 for 1 emerald, so string sold to him can fund arrows bought straight back.

Also on the Fletcher's list: crossbow, feather, enchanted bow, tripwire hook, enchanted crossbow, tipped arrow.

Spiders drop it, cobwebs cut with shears give it, and a fishing rod pulls it up as junk, so string arrives without being farmed. Its uses are all structural: bows, fishing rods, leads, looms, scaffolding and the wool that beds and banners are made of.

Four string make one wool, which matters when a build needs a colour and there is no sheep nearby. As a tripwire it becomes a redstone component, which is the one place string does something other than sit inside a recipe.

Placed on the ground string is nearly invisible and blocks nothing, but a mob walking through it triggers a tripwire and, more usefully, string placed under a block stops a mob spawning there in some builds.

Four string make wool, which is the only way to get wool without a sheep, and that recipe has saved more than one player their first night when there were spiders and no animals.

It is also what a bow, a crossbow, a fishing rod, a lead and a loom all need, which is a lot of different systems depending on the same spider.

Emptying both buyers takes 544 String before either restocks: 224 for the Fletcher and 320 for the Fisherman. That much String is spider work. How to Build a String Farm in Minecraft gathers it from a spider farm while you stand nearby, and a spider spawner found underground does the same job with experience on top: How to Build a Mob Spawner XP Farm in Minecraft.