Agent Skills: MultiversX Entry Point Analyzer

MultiversX Entry Point Analyzer

This skill helps you identify the attack surface of a smart contract by enumerating all public interaction points.

1. Identification

Scan for multiversx_sc macros that expose functions:

• #[endpoint]: Public write function. High Risk.
• #[view]: Public read function. Low risk (unless used on-chain).
• #[payable]: Accepts EGLD/ESDT. Critical Risk (value handling).
• #[init]: Constructor.
• #[upgrade]: Upgrade handler. Critical Risk (migration logic).

2. Risk Classification

A. Non-Payable Endpoints

Functions that change state but don't accept value.

• Check: Is there require!? Who can call this (Owner only?)?
• Risk: Unauthorized state change.

B. Payable Endpoints (#[payable])

Functions receiving money.

• Check:
  • Does it use self.call_value().all() or self.call_value().single()?
  • Is amount > 0 checked?
  • Are token IDs validated?
• Risk: Stealing funds, accepted fake tokens.

C. Views

• Check: Does it modify state? (It shouldn't, but Rust allows interior mutability or misuse).

3. Analysis Workflow

1. List all Entry Points.
2. Tag Access Control: OnlyOwner, Whitelisted, Public.
3. Tag Value handling: Refusable, Payable.
4. Graph Data Flow: Which storage mappers do they touch?

4. Specific Attacks

• Privilege Escalation: Is a sensitive endpoint accidentally public?
• DoS: public endpoint inserting into UnorderedSetMapper (unbounded growth).

Output Format

Entry Point Inventory

| # | Endpoint | Type | Payable | Access Control | Risk Level | Storage Touched | Location |
|---|----------|------|---------|----------------|------------|-----------------|----------|
| 1 | stake | endpoint | EGLD | Public | Critical | user_stake, total_staked | src/lib.rs:42 |
| 2 | claim | endpoint | No | Public | High | user_rewards | src/lib.rs:87 |
| 3 | set_fee | endpoint | No | #[only_owner] | Medium | fee_percent | src/admin.rs:12 |
| 4 | get_balance | view | No | Public | Low | - | src/views.rs:5 |
| 5 | init | init | No | Deploy only | Critical | all mappers | src/lib.rs:1 |

Attack Surface Summary

Total endpoints: [N]
  Critical (payable/init/upgrade): [N]
  High (state-changing, public): [N]
  Medium (state-changing, restricted): [N]
  Low (views): [N]

Unchecked payable endpoints: [list or "none"]
Public state-changing without access control: [list or "none"]
Endpoints missing from Mandos scenarios: [list or "none"]

Completion Criteria

Entry point analysis is complete when:

1. Every #[endpoint], #[view], #[payable], #[init], #[upgrade], and #[callback] is in the inventory table.
2. Every entry has a risk classification.
3. Attack Surface Summary is filled.
4. Any endpoint that is payable without token validation is flagged.