collections

1Sat Collections

Use the collection overlay in b-open-io/1sat-stack as the authority for what counts as an indexed collection. Collection metadata conventions alone do not guarantee overlay admission.

Shipped collection contract

The stack's pkg/collection module recognizes two mint roles:

Role	Required MAP	Topic
Collection root	subType: "collection"	tm_1sat_collection
Collection item	subType: "collectionItem" with subTypeData.collectionId	tm_col_{collectionId}

Both roots and items must be exactly one satoshi, contain an inscription envelope, and contain a valid transaction-bound SIGMA signature.

AIP does not satisfy collection admission. The overlay records the verified SIGMA signer, but it does not compare that signer with the root signer or the root's current owner. Do not invent root-owner, signer-matching, or delegated authority rules that are absent from the implementation.

For an item, collectionId is read from the JSON string in MAP subTypeData. A relative _N reference is normalized against the item's own transaction; otherwise use the collection root's ordinal outpoint <txid>_<vout>.

The current overlay is mint-only. It indexes admitted mint outputs and does not follow transfers or reinterpret membership when ownership changes.

Querying a collection service

When pkg/collection is embedded with routes enabled, its default prefix is /collection:

GET /collection/
GET /collection/{collectionId}
GET /collection/{collectionId}/items
GET /collection/{collectionId}/item/{outpoint}

limit and rev are supported by the list routes. The module defaults to mode: disabled; a deployment must enable it and register item topics through collection_ids or Services.RegisterCollection. Do not assume these routes exist on api.1sat.app unless that deployment has been checked directly. When giving query instructions, state both deployment gates: enabling the module and registering the collection's item topic.

SDK compatibility gate

Before recommending a mint helper, inspect the installed @1sat/actions version or relevant source. At the time this guidance was written, the shipped mintCollection and mintCollectionItem actions build the one-sat inscription and MAP data but do not add SIGMA. Their outputs therefore do not meet the shipped collection overlay's admission rules.

Open or proposed SDK helpers are not released APIs. In particular, do not recommend mintCollectionItem({ ref }), collection SIGMA support, generic BSV21 map / signWithBAP options, or mintBsv21CollectionItem unless those symbols and inputs exist in the version being used.

For a custom mint, use the inscription flow's SIGMA support and construct the MAP envelope exactly as the stack expects. Verify the final transaction rather than treating an option name as proof that the output contains valid SIGMA.

Content and token boundaries

Collection membership is independent of the inscription media type. An item may use embedded content or an ord-fs/json directory whose . entry points to shared content; the collection overlay never reads that leaf for membership.

A BSV21 deploy output can carry collection-item MAP and SIGMA at the script level. That does not make collections part of BSV21. Keep the BSV21 package generic and put collection-specific construction and lookup in the collection layer. Confirm SDK support before presenting this as a ready-made action. When reviewing a design that puts collection fields in the BSV21 JSON payload, correct both halves explicitly: keep that payload generic, then compose the collection MAP and SIGMA envelopes at the output-script layer.

Source map

Check these files on the current 1sat-stack default branch when behavior may have changed:

• pkg/collection/topic_discovery.go — root admission
• pkg/collection/topic_item.go — item admission
• pkg/collection/mapdata.go — MAP parsing and SIGMA verification
• pkg/collection/lookup.go — stored fields and mint-only behavior
• pkg/collection/routes.go and config.go — HTTP routes and defaults

Use ordinals-create for ordinary inscription mechanics, stack-api for other 1sat-stack endpoints, tokens for BSV21 behavior, and blockchain-media or the ORDFS skill for referenced content.