JetBrains Releases MCP Server for WebAssembly Analysis

LLMs are prone to hallucination when analyzing low-level details of WebAssembly (Wasm) binaries, such as LEB128 indices and call_indirect targets. To address this, JetBrains has released the Hexana MCP server, which combines model reasoning with the tool's deterministic parsing.

Key features of the Hexana 0.2.0 update are as follows:

• Granular Tool Provision: Moving away from the existing comprehensive query approach, it provides a catalog of self-describing MCP tools so Claude can select the appropriate tool for the context.
• Key Features:
  • Crash Analysis: Maps funcidx values in the stack to function IDs and memory write/host call effects
  • Build Comparison (Diff): Checks API/ABI changes, signature changes, and public type indices
  • Supply Chain Audit: Inspects host functions imported by the module (env, wasi_*, etc.) and sandbox requirements
  • Surface Inspection: Checks exports, memory contracts, mutable/imported globals, and data segment payloads
  • Component Inspection: Checks dependencies and compatibility drift
• Efficiency: Output data is byte-limited and paginated, enabling processing of large modules that would be difficult to fit within a context window.
• Installation: Can be installed within Claude Code via the /plugin marketplace add JetBrains/hexana command, and requires a Java 21+ runtime.