claude-dev-suite Inscriptions
Casey Rodarmor's scheme (Jan 2023) for embedding arbitrary data on Bitcoin via Taproot script-path commitments. Combined with ordinals, each inscription is "owned by" a specific sat.
Mechanism
1. Construct a Taproot script tree containing an "envelope" leaf:
OP_FALSE
OP_IF
OP_PUSH "ord"
OP_PUSH 1 ; field 1 = content type
OP_PUSH "image/png"
OP_PUSH 0 ; field 0 = body
OP_PUSH <data chunks>
...
OP_ENDIF
2. Commit to the script tree in a Taproot output.
3. Reveal the inscription via spending that output, using script-path:
- Witness includes the envelope + control block.
- Data appears in the witness on chain.
The data is "inscribed on" the first sat of the spent input.
Two-tx pattern
Most inscriptions use a 2-tx pattern:
- Commit tx: pay-to-Taproot output committing to envelope.
- Reveal tx: spend commit output, revealing inscription in witness.
This pattern allows re-use of prior key/script tree.
Inscription envelope fields
field 0: body (the actual data)
field 1: content_type (MIME type)
field 2: pointer (sat offset within UTXO)
field 3: parent (parent inscription ID for relationships)
field 5: metadata (CBOR-encoded)
field 7: metaprotocol (e.g., "brc-20")
field 9: content_encoding (e.g., "br" for brotli)
Recursive inscriptions
Field 6: delegate lets one inscription reference content of
another. Forms a graph; saves bytes by re-using inscribed data.
Inscription "scripts" that load JS/SVG/HTML can use
/r/inscription/<id> URLs to fetch other inscriptions on-chain.
Privacy / cost impact
Inscriptions consume witness space, which is discounted 4x in fee accounting. But they still cost real money:
- A 100 KB inscription costs ~25,000 vB ≈ a normal small block-size worth of fees.
- Big inscriptions (1+ MB images) can cost equivalent of a typical full block.
Inscription waves
- Jan 2023: launch; high fees triggered.
- May 2023: BRC-20 wave caused massive fee spike.
- Q1 2024: ongoing constant inscription activity.
- April 2024: Runes launch (different mechanism, similar effect).
Use cases
- Bitcoin NFTs — JPEG, PNG, SVG, HTML.
- BRC-20 tokens (covered separately).
- Recursive apps — JS/HTML on chain.
- Provenance — digital art ownership.
Status / criticism
Some Bitcoin developers see inscriptions as chain spam — using chain space for non-monetary data. Bitcoin Knots specifically filters inscriptions in some configurations.
Counterview: inscriptions pay full market fees, are legitimate tx, and can't be filtered without arbitrary mempool policy that deviates from consensus.
Tools
- ord client — primary creation/viewing.
- OrdinalsBot, Gamma.io, Magic Eden — services for minting + marketplace.
- OrdiScan, mempool.space — explorers with inscription view.
Common bugs
- Reveal tx must spend the commit's output; if you spend a different output, no inscription is created.
- Sat tracking: ord computes which sat owns the inscription (first sat of first input). Mistakes here lose the inscription's identity.
- Content too large: many providers reject > a few MB.