move-safety-core-directives

Agent Building

Lightweight core directives for Sui Move always-required skills - injected into every breadth agent. Full methodology lives in the dedicated Move-Safety Agent.

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Source SKILL.md: https://github.com/PlamenTSV/plamen/blob/HEAD/agents/skills/sui/move-safety-core-directives/SKILL.md

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Move Safety Core Directives (Sui)

Purpose: These are the INVENTORY + FLAG directives extracted from the 4 always-required Sui skills (ABILITY_ANALYSIS, BIT_SHIFT_SAFETY, TYPE_SAFETY, OBJECT_OWNERSHIP). Every breadth agent receives these to flag Move-specific patterns for depth review. The full trace methodology lives in the dedicated Move-Safety Agent (spawned separately). Total: ~155 lines (vs ~900 lines for 4 full skills)

1. Ability Inventory (from ABILITY_ANALYSIS)

Enumerate ALL structs. For each:

Module	Struct	Abilities	Has `id: UID`?	Is Object?	Transferable?	Notes

Flag for depth review:

Struct with copy that holds Balance<T> or represents economic value -> [FLAG:ABILITY-COPY-VALUE]
Struct with drop that represents an obligation (receipt, hot potato) -> [FLAG:ABILITY-DROP-OBLIGATION]
Receipt/hot potato consumed against an object without checking a stored source object ID (order_id, pool_id, position_id, loan_id) -> [FLAG:RECEIPT-ID-MISMATCH]
Object (key) with store that should restrict transfers -> [FLAG:ABILITY-EXCESS-STORE]
Hot potato (no abilities) with no consumption path in the protocol -> [FLAG:ABILITY-STUCK-HOTPOTATO]
copy + key combination (impossible in Sui; compilation error) -> [FLAG:ABILITY-INVALID-COMBO]

2. Bit Shift Inventory (from BIT_SHIFT_SAFETY)

GREP: Search all .move files for << and >>.

For each shift operation:

Location	Operand Type	Bit Width	Shift Amount Source	User-Controllable?	Bounded?

Flag for depth review:

Shift amount is user-controllable or computed AND unbounded -> [FLAG:SHIFT-UNBOUND]
Shift amount is constant but >= bit width -> [FLAG:SHIFT-OVERFLOW-CONST]
Shift in public/entry function with external input path -> [FLAG:SHIFT-EXTERNAL]

3. Generic Type Inventory (from TYPE_SAFETY)

GREP: Search all .move files for fun .*< to find every generic function.

For each generic function:

Function	Module	Type Params	Constraints	Entry?	Creates/Destroys T?

Flag for depth review:

Generic function accepting Coin<T> or Balance<T> without verifying T matches expected type -> [FLAG:TYPE-COIN-CONFUSION]
Generic function accepting both T and a runtime selector/config/index/object (asset id, pool id, position id) without binding them together -> [FLAG:TYPE-CONFIG-MISMATCH]
Generic with only store constraint where key or specific type is needed -> [FLAG:TYPE-WEAK-CONSTRAINT]
Generic entry function callable by anyone with attacker-chosen type -> [FLAG:TYPE-ATTACKER-CHOSEN]
One-Time Witness (OTW) type used outside init() or not consumed -> [FLAG:TYPE-OTW-LEAK]

4. Move Reference Assignment Inventory

GREP: Search all .move files for destructuring from mutable references and assignments between destructured names:

let Struct { ... } = <expr returning &mut Struct>
assignments inside the same function where the left-hand identifier came from a &mut destructure
reset/accounting code that uses left = limit, remaining = cap, field_ref = other_ref instead of *left = *limit

For each candidate:

Function	Destructured Ref Fields	Assignment	LHS Dereferenced?	RHS Dereferenced?	Intended Field Written?

Flag for depth review:

Assignment to a mutable reference variable without * on the LHS when the intent is to update the stored field value -> [FLAG:REF-REASSIGN-WRONG-FIELD]
Destructured mutable reference later reassigned to another field reference, causing writes to affect the wrong field -> [FLAG:REF-ALIAS-CORRUPTION]
Epoch/limit/cooldown/quota reset logic using field references where value copy was intended -> [FLAG:REF-RESET-BUG]

5. Object Ownership Inventory (from OBJECT_OWNERSHIP)

Classify every object (key ability) by ownership model:

Object	Ownership	Created Via	Has `store`?	Transfer Restricted?	Dynamic Fields?

Flag for depth review:

Shared object mutated without access control -> [FLAG:OBJ-SHARED-UNGUARDED]
public function returns &mut or exposes borrow_mut/dynamic-field mutable access to internal sensitive state without a capability or public(package) restriction -> [FLAG:OBJ-PUBLIC-MUT-REF]
Object with store that should NOT be freely transferable -> [FLAG:OBJ-EXCESS-TRANSFER]
Object deleted via object::delete without cleaning up dynamic fields -> [FLAG:OBJ-DELETE-DIRTY]
Owned object wrapped/unwrapped in ways that change its accessibility -> [FLAG:OBJ-WRAP-ESCAPE]
Object with Balance<T> field but no withdrawal function -> [FLAG:OBJ-STRANDED-BALANCE]

Self-Check

Before completing analysis, verify you produced inventories for ALL 5 sections above. Missing inventories = missing coverage for Move-specific vulnerability classes.