# Mezcal

Runes-lite JSON mezcalstones in OP_RETURN from block 898,750; BTI's decoder transcribes the author's reference indexer, quirks and all.

URL: https://blockspace.wiki/protocols/mezcal/

Mezcal is a fungible token protocol. In [BTI](https://blockspace.wiki/glossary/bti/)'s token table its tokens are Mezcals, each identified by a mezcal id `block:tx`. The name is an alias, unique by protocol rule. The genesis mezcal is `mezcal/1:0`, named `taco`. BTI is its indexer: it is a [native protocol](https://blockspace.wiki/glossary/native-protocol/), read by BTI's own mezcal decoder.

## How Mezcal writes to Bitcoin

The roster describes Mezcal as "runes-lite JSON mezcalstones": JSON messages in an [OP_RETURN](https://blockspace.wiki/glossary/op-return/), with etchings, mints and edicts shaped like those of [Runes](https://blockspace.wiki/glossary/rune/). Its genesis block is 898,750. The genesis mezcal at `1:0` is hardcoded: `taco`, with an amount of 1e10 per mint and a cap of 21,000 mint events. The ruleset records that 25,919 mints of it are on chain, so the cap decides about 5,000 of them. Mints can be priced: every price term must be paid to its `pay_to` in full, and a flex mint (amount 0 with a price) mints the amount received divided by the price.

## How BTI attributes its bytes

The decoder is a transcription of the protocol author's reference indexer (https://github.com/bitapeslabs/mezcal, pinned to one revision), the same stance BTI takes with Runes, where it transcribes ord's rune updater. Its JavaScript coercion quirks are ported as the writer's rule (U2):

- amounts parse as JavaScript BigInt, so `"0x10"` is 16;
- the symbol is one code point;
- the mezcalstone schema is strict, so an unknown key makes it a [cenotaph](https://blockspace.wiki/glossary/cenotaph/);
- any unparseable first OP_RETURN in a transaction that carries mezcal balances is a cenotaph that burns them;
- mint ids are normalised through `Number()` (`"01:0"` becomes `"1:0"`), but edict ids are not.

The roster says every block is walked, because balances drift through plain spends, and unrelated OP_RETURNs can burn them. The first mezcal-shaped carrier, at block 898,685, came 65 blocks before genesis and indexes as nothing.

Mezcal entered the roster on 2026-08-11 through ruling U3's transferability gate. The gate's evidence: a mint of 1e10 `taco` onto an output at block 898,763, then an edict at 898,768 that spends it, clamps its 2e10 ask to the 1e10 available, and lands it on a different script.

## Findings of the August review

The BTI protocol review of 2026-08-29 confirmed the cap. 4,981 mints hit the closed `taco` cap within 625 blocks of genesis and were recorded as [attempts](https://blockspace.wiki/glossary/attempt/), within 19 rows of the ruleset's estimate. Other attempts were 6 cenotaphs, 3 taken names and 1 unknown token. The review found Mezcal alive but sparse, with its last claim then at block 964,603.

It also found 11 of 49 mezcal token identities, all etchings between blocks 898,778 and 901,414, with no claim, no attempt and no aggregate. Under rules U2 and U5 a token with no grounded record should not exist; the review judged the mechanism probable, an etching that registers its token before an early return.

## Live figures

Mezcal holds 6,561,376 bytes in Book A and 0 in Book C. The books count 38 mezcals across 29,807 operations, from block 898750 to 972033 (as of block 972,299, 2026-10-20 09:30:48 UTC).

Sources:

- Blockspace Holdings records
- block.space protocols API · https://block.space/api/protocols

Live figures: protocols as of block 972,299, 2026-10-20 09:30:48 UTC

Updated: 2026-10-20