# Minecraft Snbt Format

> SNBT Format

- Skill: `zmjjkk123-hub/minecraft-snbt-format` (Agent Skill)
- Install (CLI): `npx skillmds@latest add zmjjkk123-hub/minecraft-snbt-format`
- Raw SKILL.md: https://api.skillmd.com/api/skills/zmjjkk123-hub/minecraft-snbt-format/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: ZMJJKK123-hub (https://skillmd.com/u/zmjjkk123-hub)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/zmjjkk123-hub/minecraft-snbt-format

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# SNBT Format

SNBT (Stringified Named Binary Tag) is the text form of NBT, used in data-modifying commands and `.snbt` files (UTF-8). It resembles NBT but is not identical to it. `/data get` prints syntax-highlighted SNBT ("pretty-printed"); the `nbt` text component type can also output highlighted SNBT.

## Data Types

### Numbers

Underscores may separate digits (`0b10_01`, `0xAB_CD`, `1_2.3_4__5f`, `1_2e3_4`) but not at the start/end.

- **Floats** (IEEE 754): no-suffix decimals are doubles (`1.2`). Fractional or integer parts may be omitted (`.1`, `1.`). Scientific notation allowed (`1.2e3`, `12000e-1` → 1200.0). Out-of-range (→ infinity) values like `1e1000` are invalid. NaN/Inf/hex floats unsupported.
- **Integers**: no-suffix integers are ints (`123`). Hex `0x` and binary `0b` prefixes allowed (`0xCAFE`, `0b101`). Integers (except 0) must not start with `0` (octal ambiguity).
- **Booleans**: SNBT booleans are bytes limited to 0/1; `true`/`false` (case-insensitive) → 1b/0b.

### Type Suffixes

First letters, case-insensitive: `b` byte, `s` short, `i` int, `l` long (floats: `f`, `d`). Optionally prefixed with `s`/`S` (signed) or `u`/`U` (unsigned) — e.g. `123sb` = signed byte 123. Signed values store as two's complement; the prefix only affects parse ranges (`240sb` fails; `240ub` == `-16sb`). Decimal numbers default to signed; hex/binary default to unsigned. Because `b` is a valid hex digit, hex bytes need the explicit prefix (`0x11ub`, `0x11sb`).

### Strings

- Quoted: `"test"` or `'test'`; the same quote inside must be escaped (`"\"test"` valid, `""test"` invalid).
- Unquoted: `test` — only `0-9`, `a-zA-Z`, `.`, `_`, `+`, `-`; must not start with a digit, `.`, `+`, or `-` (numeric conflicts); `true`/`false` parse as booleans.
- Escape sequences in quoted strings: `\"`, `'`, `\\`, `\/`, `\b`, `\f`, `\n`, `\r`, `\t`, `\uXXXX` (Unicode escapes).

### Arrays

`[B;...]`, `[I;...]`, `[L;...]`: values without suffixes take the array's type (`[B;1,2]` == `[B;1b,2b]`); smaller types are widened (`[I;1b,2s,3]` == `[I;1i,2i,3i]`).

### Lists

Heterogeneous elements allowed (`['', {text:"hello"}, 123]`; some contexts still require homogeneity). One trailing comma allowed after a valid element (`[1,2,]`; `[,]`, `[1,,]` invalid). Nesting ≤ 512 levels.

### Compounds

Key-value maps (`{a:b}`). One trailing comma allowed (`{a:b,}`; `{,}`, `{a:b,,}` invalid). Nesting ≤ 512 levels.

## SNBT Operations

Function-like syntax `<name>(<arg1>, ...)` evaluated at parse time (cannot be preserved or syntax-highlighted):

- `bool(arg)` — exactly one numeric or boolean argument: booleans pass through; numbers → true if non-zero. `bool(true)` → true; `bool(0)` → false; `bool("foo")` → error.
- `uuid(str)` — one dash-formatted UUID hex string → int array: `uuid("f81d4fae-7dec-11d0-a765-00a0c91e6bf6")` → `[I; -132296786, 2112623056, -1486552928, -920753162]`.

## Conversion

SNBT is never stored directly — it converts to NBT, then to program objects (see the nbt-format skill).