Insurance Coverage System

[ope-olawale]

Insurance Coverage System - Smart Contract Description

Summary

The Insurance Coverage System is a decentralized insurance protocol built on the Stacks blockchain using Clarity smart contract language. It enables users to purchase insurance coverage by paying premiums in STX tokens and subsequently file claims against their purchased policies. The contract operates autonomously, managing a reserve fund from collected premiums and processing claims based on predefined coverage limits.

Core Functionality

Policy Purchase Mechanism

Users can acquire insurance coverage by calling the purchase-coverage function with two parameters: the desired coverage amount and policy duration. The contract automatically calculates the required premium using the formula: Premium = Coverage Limit × (1/100) × Duration. Upon payment, the premium is transferred to the contract's reserve fund, and a policy record is created containing the coverage limit, premium paid, and expiry block height.

Claim Processing

Policyholders can file claims through the file-claim function by specifying the claim amount. The contract validates that:

• The claimant has an active policy
• The claim amount does not exceed their coverage limit
• The reserve fund has sufficient balance to honor the claim

Upon successful validation, the claim amount is transferred from the reserve fund to the claimant, and a claim record is created with approval status.

Administrative Controls

The contract owner (set at deployment) has elevated privileges to create custom policies via the create-policy function, allowing manual specification of coverage limits, premiums, and durations. This enables flexible policy configuration beyond the standard automated premium calculation.

Technical Architecture

Data Storage

The contract utilizes two primary data maps:

• insurance-policies: Stores active policies mapped to policyholder principals, containing coverage-limit, premium, and expiry data
• claim-submissions: Records processed claims with claim amounts and approval status

A single data variable reserve-fund maintains the aggregate balance of all collected premiums and available funds for claim payouts.

Safety Constraints

The contract enforces several safety parameters:

• Maximum Coverage Limit: 1,000,000,000 micro-STX per policy
• Maximum Duration: 52,560 blocks (approximately 1 year)
• Minimum Premium: 1,000 micro-STX to ensure economic viability
• Overflow Protection: Arithmetic checks prevent integer overflow during premium accumulation

Error Handling

The contract implements comprehensive error handling with five distinct error codes covering authorization failures, invalid parameters, insufficient funds, missing policies, and invalid claims. All state-changing operations validate inputs and fund availability before execution.

Use Cases

This smart contract is suitable for:

• Decentralized insurance pools where users collectively fund and claim from a shared reserve
• Peer-to-peer coverage agreements without intermediaries
• Transparent insurance operations with on-chain verifiability
• Automated claim processing based on smart contract logic
• Community-driven protection schemes with programmable parameters

Key Advantages

1. Transparency: All policies, claims, and fund balances are publicly verifiable on-chain
2. Automation: Premium calculation and claim processing occur automatically without manual intervention
3. Decentralization: No central authority controls fund disbursement; claims are processed programmatically
4. Immutability: Policy terms are enforced by smart contract code and cannot be arbitrarily changed
5. Cost Efficiency: Eliminates traditional insurance overhead by removing intermediaries

Limitations & Considerations

• No Policy Expiry Enforcement: The contract does not automatically invalidate expired policies; expiry checking must be implemented externally
• Simple Claim Validation: Claims are approved automatically if coverage is sufficient; no fraud detection or claim verification mechanism exists
• Fixed Premium Formula: The premium calculation uses a basic linear formula without risk assessment
• Single Claim Per User: The claim map structure allows only one recorded claim per principal
• No Refunds: Premiums are non-refundable; no cancellation mechanism is provided
• Reserve Fund Dependency: The system relies on adequate reserve fund balance; insolvency is possible if claims exceed collected premiums

Integration Points

External systems can integrate with this contract by:

• Querying policy details via get-policy-details for coverage verification
• Monitoring the reserve fund balance through get-fund-balance for solvency assessment
• Tracking claim history using get-claim-details for audit purposes
• Building user interfaces that call purchase-coverage and file-claim functions
• Implementing policy expiry checks by comparing current block-height against policy expiry values

Security Model

The contract employs a trust-minimized security model where:

• Funds are held in the contract address and managed programmatically
• Only the contract owner can create custom policies (preventing unauthorized policy manipulation)
• Premium transfers use the native stx-transfer? function with error propagation
• Claim payouts use as-contract context to transfer from the contract's balance
• Arithmetic overflow protection prevents fund accounting errors