Module ucan 

SP-capability-v2 UCAN-lite implementation.

UCAN-lite is a profile of UCAN v1.0 narrowed for ATD’s use case:

• JWT compact form on the wire (not DAG-CBOR / CIDv1).
• alg = "EdDSA", typ = "ucan/1.0+jwt", ucv = "1.0".
• did:key issuer / audience only (no did:web, no did:plc).
• Capabilities tunneled as cmd = "atd-cap", args.caps: Vec<String>, args.with: Vec<{patient: String}> (or other binding kinds reserved).

Phasing (per docs/archive/superpowers/plans/2026-05-11-sp-capability-v2.md):

• Phase B.1 (parse): structural decoder; no signature, no chain walk.
• Phase B.2 (verify, not yet landed): chain attenuation, signature verification (Ed25519), audience pinning, depth limit, revocation consultation. Lands in a follow-up commit on the same SP.

Spec: docs/archive/superpowers/specs/2026-05-11-sp-capability-v2-design.md §4.1–§4.7

Re-exports

pub use error::UcanParseError;

pub use error::UcanVerifyError;

pub use error::wire_code;

pub use parse::parse_jwt;

pub use revocation::InMemoryUcanRevocationStore;

pub use revocation::UcanRevocationStore;

pub use types::UcanCapability;

pub use types::UcanHeader;

pub use types::UcanPayload;

pub use verify::VerifyConfig;

pub use verify::compute_cid;

pub use verify::verify_jwt;

pub use verify::verify_tokens;

Modules

error

UCAN-lite parse / verify errors.

parse

SP-capability-v2 Phase B.1 — JWT compact-form structural decoder.

revocation

SP-capability-v2 revocation-store trait + reference impl.

types

UCAN-lite payload types.

verify

SP-capability-v2 Phase B.2 — UCAN-lite signature + chain verifier.