Contract Splitting Recommendation Tool (Size Limit)

WHAT IT DOES

Contract Splitting Recommendation Tool (Size Limit) analyzes smart contract bytecode, ABIs, and structural dependencies to recommend splitting large contracts that approach or exceed the EIP-170 size limit of 24,576 bytes. It retrieves on-chain contract bytecode via eth_getCode and fetches verified source code and ABI from block explorer APIs to extract function signatures, state variable dependencies, event definitions, and modifier structures. The tool measures the deployed bytecode size and compares it against the EIP-170 limit, calculating remaining capacity. It then builds a state dependency graph, clustering functions by shared state access to identify natural module boundaries. The output includes total bytecode size, remaining capacity, a visual size indicator, suggested module groupings with estimated sizes and contained functions, and a list of actionable recommendations—such as moving non-core functions to libraries or child contracts, adopting proxy patterns, or separating storage from logic. This enables developers to proactively manage contract size before reaching deployment limits.

HOW TO USE

Connect your BGWallet to the target EVM chain. Paste the address of the contract you wish to analyze for size-related splitting opportunities. Optionally supply a GitHub repository URL to pull existing module definitions, upgrade documentation, or splitting patterns for additional context. The tool fetches the contract's bytecode and ABI, calculates the deployed size, builds a dependency graph, and performs clustering analysis to identify cohesive function groups. Review the suggested module groupings, the size bar visualization, and the list of recommendations. Use the audit results to guide refactoring efforts, splitting large contracts into multiple smaller modules that remain under the EIP-170 limit while preserving logical cohesion and minimizing cross-module coupling.

BYTECODE SIZE AND STRUCTURAL DECOMPOSITION ENGINE

The real technical mechanism is the bytecode size and structural decomposition engine that combines precise size measurement with semantic clustering. The tool first retrieves the deployed bytecode via eth_getCode and measures its exact length in bytes, providing a baseline against the 24,576-byte limit. It then parses the ABI and source code to construct a state dependency graph, where nodes represent functions and edges connect functions that access the same state variables. The graph is weighted by the bytecode contribution of each function, estimated from the ABI and source code metadata. The tool applies a recursive bisection algorithm that attempts to partition the graph into subgraphs that each fit within a configurable size target—typically 80% of the EIP-170 limit to provide safety margin. The algorithm balances three objectives: minimizing cross-module state dependencies, keeping each module under the size limit, and preserving logical cohesion (functions that are called together or share state should stay together). The output includes estimated bytecode size for each proposed module, derived from the sum of its constituent functions' estimated contributions, plus overhead for dispatch logic. This approach reduces the risk of deployment failures due to oversized contracts and improves maintainability through modular design, catching size issues that would otherwise only surface during deployment.

WHAT IT CANNOT SEE

This tool cannot recommend splitting without access to contract bytecode or ABI. It is limited by your RPC provider's rate limits for bytecode retrieval, which may delay analysis on congested networks. It cannot detect logical coupling that does not manifest in the ABI or bytecode size—for example, functions that must be called in a specific order or that share implicit invariants not reflected in state variable access. The recommendations rely on the completeness of the ABI and source code verification; unverified contracts or incomplete verification data will produce incomplete or inaccurate suggestions. Recommendations are based on structural analysis and may not capture all semantic cohesion or coupling issues, such as functions that are conceptually related but operate on different state variables. The tool cannot assess the quality or appropriateness of proposed module boundaries—it suggests clusters based on state access and size, but these clusters may not align with business logic or domain boundaries. It may produce false positives for contracts that are near the size limit but logically cohesive, suggesting splitting when refactoring might be unnecessary. The tool does not execute the contract to validate splitting recommendations; all suggestions should be reviewed in the context of the contract's intended behavior. It cannot account for deployment costs or gas optimization trade-offs across multiple contracts, such as increased gas costs for cross-module calls.

PLEASE NOTE

This tool works exclusively with EVM-compatible chains. It requires active internet connectivity to access block explorer APIs and RPC endpoints. Some block explorers may require API keys for high-volume bytecode retrieval. The tool is read-only and does not modify or deploy any code—it only produces analysis and recommendations. Always review splitting recommendations against your specific contract's logic, upgrade strategy, and business requirements before refactoring production contracts.