diff --git a/csrc/helloworld/README.md b/csrc/helloworld/README.md
index 1249fe50b..bd4655b27 100644
--- a/csrc/helloworld/README.md
+++ b/csrc/helloworld/README.md
@@ -1,5 +1,5 @@
 ##### Description of Helloworld
-This is an extreme simple example of writing an op on Ascend NPU.
+This is an extremely simple example of writing an op on Ascend NPU.
 
 A typical op includes two major parts:
 * Device part which really running device, i.e. NPU
diff --git a/docs/developer_guide/contribution_guide.md b/docs/developer_guide/contribution_guide.md
index f99be1564..23355fe42 100644
--- a/docs/developer_guide/contribution_guide.md
+++ b/docs/developer_guide/contribution_guide.md
@@ -2,6 +2,8 @@
 
 Welcome to **SGL-KERNEL-NPU**! We appreciate your interest in contributing. This guide provides a concise overview of how to set up your environment, run tests, build documentation, and open a Pull Request (PR). Whether you’re fixing a small bug or developing a major feature, we encourage following these steps for a smooth contribution process.
 
+**SGL-KERNEL-NPU** is a kernel library for LLM inference engines, which provides optimized compute primitives (including Ascendc and Triton) especially for engines running on NPU. It has been used by [SGLang](https://github.com/sgl-project/sglang).
+
 ## Install SGL-KERNEL-NPU from Source
 
 ### Fork and clone the repository
@@ -16,42 +18,50 @@ git clone https://github.com/<your_user_name>/sgl-kernel-npu.git
 
 Refer to [Install SGL-KERNEL-NPU from Source](../../python/sgl_kernel_npu/README.md).
 
-## Format code with pre-commit
+## Ascend C Kernel Contribution
 
-We use [pre-commit](https://pre-commit.com/) to maintain consistent code style checks. Before pushing your changes, please run:
+### Steps to add a new Ascend C kernel:
 
-```bash
-pip3 install pre-commit
-pre-commit install
-pre-commit run --all-files
-```
+1. Implement the kernel in [csrc](https://github.com/sgl-project/sgl-kernel-npu/tree/main/csrc). You can start by reading the [helloworld](https://github.com/sgl-project/sgl-kernel-npu/tree/main/csrc/helloworld) kernel, a simple example of adding two bf16 vectors. If you are new to this, the [Ascend C Kernel Development Guide](https://www.hiascend.com/document/detail/zh/CANNCommunityEdition/850alpha001/opdevg/Ascendcopdevg/atlas_ascendc_10_0001.html) could also be helpful.
 
-- **`pre-commit run --all-files`** manually runs all configured checks, applying fixes if possible. If it fails the first time, re-run it to ensure lint errors are fully resolved. Make sure your code passes all checks **before** creating a Pull Request.
-- **Do not commit** directly to the `main` branch. Always create a new branch (e.g., `feature/my-new-feature`), push your changes, and open a PR from that branch.
+2. Expose the interface in [include/sgl_kernel_npu_ops.h](https://github.com/sgl-project/sgl-kernel-npu/blob/main/include/sgl_kenel_npu_ops.h)
 
-## Run and add unit tests
+3. Create torch extension in [pytorch_extensions.cpp](https://github.com/sgl-project/sgl-kernel-npu/blob/main/csrc/pytorch_extensions.cpp)
 
-If you add a new feature or fix a bug, please add corresponding unit tests to ensure coverage and prevent regression.
-SGL-KERNEL-NPU uses Python's built-in [unittest](https://docs.python.org/3/library/unittest.html) framework
+4. Update [CMakeLists.txt](https://github.com/sgl-project/sgl-kernel-npu/blob/main/csrc/CMakeLists.txt) to include new kernel source
 
-## Write documentations
+## Triton Kernel Contribution
 
+Triton kernels are located at [sgl_kernel_npu](https://github.com/sgl-project/sgl-kernel-npu/tree/main/python/sgl_kernel_npu/sgl_kernel_npu)
 
-## Test the accuracy
+## Development Tips
 
+- How to write schema: [Schema reference](https://github.com/pytorch/pytorch/blob/main/aten/src/ATen/native/README.md#func)
 
-## Benchmark the speed
+   ```cpp
+   // We need def with schema here for torch.compile
+   m.def("helloworld(Tensor x, Tensor y) -> Tensor");
+   m.impl("helloworld", TORCH_FN(sglang::npu_kernel::helloworld));
+   ```
 
+## Run and add unit tests
 
-## Request a review
+If you add a new feature or fix a bug, please add corresponding unit tests [test](https://github.com/sgl-project/sgl-kernel-npu/tree/main/tests/python/sgl_kernel_npu) to ensure coverage and prevent regression.
+SGL-KERNEL-NPU uses Python's built-in [unittest](https://docs.python.org/3/library/unittest.html) framework.
 
+## Format code with pre-commit
 
-## General code style
+We use [pre-commit](https://pre-commit.com/) to maintain consistent code style checks. Before pushing your changes, please run:
 
+```bash
+pip3 install pre-commit
+pre-commit install
+pre-commit run --all-files
+```
 
-## How to update sgl-kernel
+- **`pre-commit run --all-files`** manually runs all configured checks, applying fixes if possible. If it fails the first time, re-run it to ensure lint errors are fully resolved. Make sure your code passes all checks **before** creating a Pull Request.
+- **Do not commit** directly to the `main` branch. Always create a new branch (e.g., `feature/my-new-feature`), push your changes, and open a PR from that branch.
 
 
-## Tips for newcomers
 
 Thank you for your interest in SGL-KERNEL-NPU. Happy coding!