kirkderp/rbinilspy

# rbinilspy [](LICENSE) [](rust-toolchain.toml) [](https://dotnet.microsoft.com) MCP server for ILSpy-based .NET assembly analysis. `rbinilspy` manages persistent ILSpy sessions with an in-memory C# worker process, loads .NET assemblies for analysis, and exposes 17 tools as named [Model Context Protocol](https://modelcontextprotocol.io) tools over stdio. ## Tools **Session Management** - `dn_open` / `dn_close` / `dn_sessions` -- open/close/list persistent ILSpy sessions - `dn_metadata` -- assembly metadata: types count, namespaces count **Discovery & Navigation** - `dn_namespaces` -- list namespaces with type counts, filter, and pagination - `dn_types` -- list types with name/namespace filter and pagination - `dn_search` -- search types or cached member names by substring - `dn_type_info` -- type metadata: base types, interfaces, attributes, modifiers **Decompilation** - `dn_decompile` -- full type decompilation to C# (with result caching) - `dn_decompile_method` -- decompile a single method (token-efficient, no full type dump) - `dn_members` -- list methods/properties/fields (with result caching) - `dn_il` -- raw CIL disassembly - `dn_search_source` -- grep decompiled C# source for a pattern **Assembly Analysis** - `dn_references` -- external assembly dependencies - `dn_usages` -- find usages of a pattern across decompiled types - `dn_resources` -- list embedded resources - `dn_raw_cmd` -- passthrough for arbitrary ilspycmd invocations ## Requirements - **.NET 10 SDK** (for worker build) - **ILSpy CLI** -- `dotnet tool install -g ilspycmd` - **Rust stable** toolchain (for building the MCP server) ## Quick Start # Build the C# worker cd ilspy-worker && dotnet publish -c Release -o bin/publish # Build and run the MCP server cd .. && cargo build --workspace RBM_CACHE_DIR=./cache cargo run -p rbm-server The server speaks the MCP protocol over stdio. Configure your MCP client: { "mcpServers": { "rbinilspy": { "command": "/path/to/rbinilspy/target/debug/rbinilspy", "args": [] } } } ## Configuration | Variable | Default | Description | | --- | --- | --- | | `RBM_CACHE_DIR` | `./rbinilspy-cache` | Cache root | | `RBM_TOOL_TIMEOUT_SECS` | 30 | Per-tool timeout (seconds) | | `RBM_ILSPY_WORKER` | auto‑detected | Path to the C# worker (binary or project dir) | | `RBM_ILSPY_CMD` | `ilspycmd` | Path to the ILSpy CLI executable | | `RBM_ILSPY_CMD_TIMEOUT_MS` | 60000 | ilspycmd subprocess timeout (milliseconds) | ## Architecture MCP Client -> stdio JSON-RPC -> rbinilspy server (Rust) -> C# worker process (stdin/stdout JSON-RPC) -> ilspycmd subprocess (per-decompilation) Assemblies are opened once and cached in the C# worker's memory. Decompiled output and member listings are cached per type for the session lifetime. ## Project Structure crates/ rbm-core/ Cache paths, config, error types rbm-server/ MCP server binary (rbinilspy) ilspy-worker/ C# persistent worker for ilspycmd ## License MIT -- see [LICENSE](LICENSE).