# 创建一个最小接口描述文件
在标准开发工作流程中，运行dfx build命令会在Canister的输出目录中创建多个文件，包括一个或多个Candid接口描述（.did）文件，这些文件处理与程序功能关联的数据类型的类型匹配。
有关用于不同数据类型的语法的详细信息，请参见Candid[规范](https://github.com/dfinity/candid/tree/master/spec)和[指导](https://sdk.dfinity.org/docs/candid-guide/candid-intro.html)。
为此程序创建一个Candid接口描述文件：
1.在您为reverse.c程序源创建的build目录中打开一个终端。
2.创建一个名为reverse.did的新文本文件。
3.添加go函数的描述。
例如：
```
service : { "go": (text) -> (text);}
```
4.保存并关闭文件。
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://mixdao.gitbook.io/dfinity/san-shou-ba-shou/4.-shi-yong-bu-tong-yu-yan-kai-fa/shi-yong-c/untitled-3.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.