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AGENTS.md

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+# AI Agent Guidelines for SOME/IP Gateway
+
+## Project Overview
+
+The S-CORE SOME/IP Gateway bridges the SCORE middleware with SOME/IP communication stacks. It's divided into two architectural components with an IPC isolation boundary:
+- **gatewayd**: Network-independent gateway logic (C++)
+- **someipd**: SOME/IP stack binding (C++)
+
+The gateway also includes Rust examples and comprehensive Python integration tests.
+
+## Code Style & Conventions
+
+**All source files must include Apache 2.0 license headers:**
+```cpp
+/********************************************************************************
+ * Copyright (c) 2026 Contributors to the Eclipse Foundation
+ *
+ * See the NOTICE file(s) distributed with this work for additional
+ * information regarding copyright ownership.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Apache License Version 2.0 which is available at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ ********************************************************************************/
+```
+
+**C++ style**: namespace organization (e.g., `score::someip_gateway::gatewayd`), includes config via FlatBuffers, uses RAII patterns for resource management.
+
+**Rust style**: Standard Rust formatting with module organization matching C++ namespaces conceptually.
+
+## Architecture & Key Patterns
+
+**Core Components:**
+- [src/gatewayd/](src/gatewayd/) - Main daemon, configuration via FlatBuffers ([gatewayd_config.fbs](src/gatewayd/etc/gatewayd_config.fbs))
+- [src/someipd/](src/someipd/) - SOME/IP binding layer
+- [src/network_service/interfaces/](src/network_service/interfaces/) - Network abstraction (message_transfer.h)
+- [examples/car_window_sim/](examples/car_window_sim/) - Complete working Rust example
+
+**Design Patterns:**
+- Configuration injection via FlatBuffers binary (see [main.cpp](src/gatewayd/main.cpp#L52) for loading pattern)
+- IPC boundaries enforce ASIL/QM context separation
+- JSON schemas validate configuration ([gatewayd_config.schema.json](src/gatewayd/etc/gatewayd_config.schema.json))
+
+## Build & Test Commands
+
+**Bazel is the primary build system.** Python 3.12 is required; pinned in MODULE.bazel.
+
+```bash
+# Build specific target
+bazel build //src/gatewayd:gatewayd
+
+# Run daemons (requires two terminals)
+bazel run //src/gatewayd:gatewayd_example
+bazel run //src/someipd
+
+# Run example application
+bazel run //examples/car_window_sim:car_window_controller
+
+# Run all tests
+bazel test //...
+
+# Run integration tests
+bazel test //tests/integration:integration
+
+# Run performance benchmarks
+bazel test //tests/benchmarks:all
+
+# Generate/update compile_commands.json for IDE support
+bazel run //:bazel-compile-commands
+```
+
+**When adding new code, tests are required by default:**
+- Integration tests in [tests/integration/BUILD.bazel](tests/integration/BUILD.bazel)
+- Use `py_pytest` rule for Python tests
+
+## Project Conventions
+
+**Directory layout**
+- Units and components are called software elements
+- Software elements are placed underneath [src/](src/)
+- A software elements directory be default looks like this:
+  ```
+  <software element>/
+  ├── BUILD
+  ├── doc/
+  ├── include/
+  ├── src/
+  └── test/```
+
+**Configuration Management:**
+- FlatBuffers schemas define typed configs (see [gatewayd_config.fbs](src/gatewayd/etc/gatewayd_config.fbs))
+- JSON schemas auto-generated for validation (tool: flatbuffers/flatc)
+- Config files loaded from binary format (see [main.cpp](src/gatewayd/main.cpp#L52))
+
+**Logging & Shutdown:**
+- Use `std::cout`/`std::cerr` for basic logging (see [main.cpp](src/gatewayd/main.cpp#L37))
+- Implement graceful shutdown with signal handlers (SIGTERM, SIGINT)
+
+**Example Pattern (Rust state machines):**
+Reference [car_window.rs](examples/car_window_sim/src/car_window.rs#L27) for window state machine implementation—shows how to structure stateful domain logic.
+
+## Integration Points
+
+**External Dependencies:**
+- `@score_communication` - SCORE middleware (IPC via mw/com)
+- `@flatbuffers` - Configuration serialization
+- `@someip_pip` - SOME/IP stack bindings in Python tests
+- `@bazel_tools_python` - Testing framework (py_pytest)
+
+**Configuration:**
+- Service instances read from [mw_com_config.json](src/gatewayd/etc/mw_com_config.json)
+- SOME/IP specifics in [vsomeip.json](tests/integration/vsomeip.json) and [vsomeip-local.json](tests/integration/vsomeip-local.json)
+
+## Security & ASIL Considerations
+
+The IPC boundary between gatewayd and someipd enforces **ASIL/QM context separation**—this is a critical architectural boundary. Changes affecting message transfer across this boundary require careful review.
+
+## Contributing
+
+Follow [CONTRIBUTION.md](CONTRIBUTION.md):
+- Use provided PR templates (bug_fix.md, improvement.md)
+- All commits must follow Eclipse Foundation rules
+- Code review via CODEOWNERS
+
+---
+
+**Last updated: 2025-04-02**