logos-co · edenbd1 · May 24, 2026
diff --git a/solutions/LP-0013.md b/solutions/LP-0013.md
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+# Solution: LP-0013 — Token Program Improvements: Authorities
+
+**Submitted by:** edenbd1
+
+## Summary
+
+Rotatable mint authority model for the LEZ Token program. Four additive instruction variants (`NewFungibleDefinitionWithAuthority`, `MintWithAuthority`, `RotateAuthority`, `RevokeAuthority`) layered on the existing token surface — pre-existing instructions and Borsh layout are untouched.
+
+Built around `lez-approval` — a self-sufficient agnostic approval library fulfilling [RFP-001](https://github.com/logos-co/rfp/blob/master/RFPs/RFP-001-admin-authority-lib.md), [published on crates.io](https://crates.io/crates/lez-approval).
+
+## Repository
+
+- **Repo:** <https://github.com/edenbd1/lp-0013-token-authorities>
+- **LEZ fork:** <https://github.com/edenbd1/logos-execution-zone/tree/lp-0013-token-authorities>
+- **Narrated video:** <https://youtu.be/Um9cVHW226E>
+
+## Approach
+
+### Architecture
+
+The authority model is layered **additively** — four new `Instruction` variants coexist with the seven originals. A new `TokenDefinition::FungibleWithAuthority` variant preserves full Borsh-layout backward compatibility (no breaking change to existing `Fungible` accounts).
+
+Authority is verified **cryptographically** via the definition account's `is_authorized` flag (set by the NSSA runtime from the transaction signature) and an `account_id` match against the stored authority. The authority is never passed as spoofable instruction data.
+
+### `lez-approval` (RFP-001)
+
+Standalone crate with zero external dependencies beyond `borsh` and `serde`:
+- `Authority(Option<[u8; 32]>)` — single-admin wrapper with terminal revocation
+- `gate()` / `rotate()` / `revoke()` — the authorization contract
+- `ApprovalError { Unauthorized, Renounced }` — documented panic payloads
+
+The `config-pda-gate` example demonstrates the library gating a non-token program's privileged config updates (RFP-001 §4).
+
+### Why the Logos stack
+
+- **Trustless execution.** Every state transition is proved in a RISC0 guest — a renounced authority is provably renounced.
+- **Censorship resistance.** Authority rotation is a standard transaction; the sequencer cannot selectively reject it.
+- **Atomicity.** LEZ's per-account read-modify-write semantics guarantee no intermediate states.
+
+### Alternatives considered
+
+- **Separate authority PDA (Solana SPL pattern):** Rejected — doubles per-tx account count with no concurrency benefit on LEZ.
+- **Modifying existing `Mint` instruction:** Rejected — breaking wire-format change. Additive variants are the correct LEZ idiom.
+- **Authority as instruction data:** Rejected after discovering the spoofing vulnerability — switched to pre_state account verification.
+- **`Result`-returning handlers:** Rejected — LEZ guest convention is panic-on-failure.
+
+## Success Criteria Checklist
+
+### Functionality
+
+- [x] **Variable-size Tokens through minting authority:** `NewFungibleDefinitionWithAuthority` sets authority at init; `MintWithAuthority` gates minting; `RotateAuthority` rotates; `RevokeAuthority` permanently revokes.
+- [x] **Three example integrations:** `examples/fixed-supply/`, `examples/variable-supply/`, `examples/config-pda-gate/` (RFP-001 §4 — gates non-token config PDA).
+- [x] **Self-sufficient agnostic library per RFP-001:** `crates/lez-approval/` — [published on crates.io](https://crates.io/crates/lez-approval). 13 unit tests. Depends only on `borsh` + `serde`.
+
+### Usability
+
+- [x] **Module/SDK:** `crates/token-authority-sdk/` re-exports key types with transaction construction docs.
+- [x] **IDL:** Two IDLs shipped — `artifacts/token.idl.json` (hand-authored, completeness) + `artifacts/token_authority.idl.spel.json` (real `spel -- generate-idl` output, provenance). Workaround rationale in `docs/SPEL_STATUS.md`.
+
+### Reliability
+
+- [x] **Atomic rotation/revocation:** Single field write or panic — no intermediate state.
+- [x] **Deterministic rejection:** `ApprovalError::Renounced` with documented error code. Confirmed on-chain: `"Guest panicked: Renounced: authority has been permanently revoked"`.
+
+### Performance
+
+- [x] **CU costs documented:** Measured via `risc0_zkvm::default_executor` (5 samples, `risc0-zkvm 3.0.5`):
+  - `MintWithAuthority`: 166,746 cycles (+42% vs baseline `Mint`)
+  - `RotateAuthority`: 124,085 cycles (+6%)
+  - `RevokeAuthority`: 101,425 cycles (−14%)
+
+### Supportability
+
+- [x] **Deployed and tested:** Full lifecycle confirmed on standalone sequencer — create (supply=1000), mint 500 (supply=1500), revoke (nonce=3), post-revoke mint REJECTED.
+- [x] **Integration tests:** 6 handler-pipeline tests + `scripts/demo.sh` for sequencer-level E2E.
+- [x] **CI green:** [GitHub Actions](https://github.com/edenbd1/lp-0013-token-authorities/actions) — build, clippy, fmt, test.
+- [x] **README:** Quickstart, architecture, CLI commands, deployment guide.
+- [x] **Demo:** `scripts/demo.sh` — 4-step lifecycle against native standalone sequencer with `RISC0_DEV_MODE=0`.
+- [x] **Narrated video:** <https://youtu.be/Um9cVHW226E>
+
+## FURPS Self-Assessment
+
+### Functionality
+Four additive instruction variants. Pre-existing instructions unchanged. Regular `Mint` explicitly rejected on `FungibleWithAuthority` tokens. `Burn` works normally. Three token patterns supported: fixed supply, variable supply, governance handoff.
+
+### Usability
+SDK re-exports key types. CLI subcommands (`new-with-authority`, `mint-with-authority`, `rotate-authority`, `revoke-authority`) in the LEZ fork wallet. Dual IDL (hand-authored + SPEL-generated). `lez-approval` on crates.io — `lez-approval = "0.1"` to consume.
+
+### Reliability
+Authority state machine has three states (active, transitioning, revoked) with no intermediate or unreachable states. 72 tests across 4 crates + integration tests. Panic-on-failure matches LEZ guest convention.
+
+### Performance
+Authority check adds one `AccountId` equality comparison per gated instruction. `FungibleWithAuthority` adds 33 bytes per definition account.
+
+### Supportability
+72 tests. CI green. 9 documentation files. CONTRIBUTING.md, SECURITY.md, NOTICE. Criteria checklist maps every requirement to evidence.
+
+## Supporting Materials
+
+- **Repo:** <https://github.com/edenbd1/lp-0013-token-authorities>
+- **LEZ fork:** <https://github.com/edenbd1/logos-execution-zone/tree/lp-0013-token-authorities>
+- **crates.io:** <https://crates.io/crates/lez-approval>
+- **Narrated video:** <https://youtu.be/Um9cVHW226E>
+- **Architecture:** [`docs/architecture.md`](https://github.com/edenbd1/lp-0013-token-authorities/blob/main/docs/architecture.md)
+- **Design decisions:** [`docs/design.md`](https://github.com/edenbd1/lp-0013-token-authorities/blob/main/docs/design.md)
+- **CU benchmarks:** [`docs/benchmarks/cu-budget.md`](https://github.com/edenbd1/lp-0013-token-authorities/blob/main/docs/benchmarks/cu-budget.md)
+- **SPEL disclosure:** [`docs/SPEL_STATUS.md`](https://github.com/edenbd1/lp-0013-token-authorities/blob/main/docs/SPEL_STATUS.md)
+- **Demo script:** [`scripts/demo.sh`](https://github.com/edenbd1/lp-0013-token-authorities/blob/main/scripts/demo.sh)
+
+## Terms & Conditions
+
+By submitting this solution, I confirm that I have read and agree to the [Terms & Conditions](../TERMS.md).