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type: reference
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# C# Documentation Best Practices

This guide provides best practices for documenting C# types using XML comments.

## Guidance for all APIs

- Use `<summary>` to provide a brief, one sentence, description of what the type or member does. Start the summary with a present-tense, third-person verb.
- Use `<remarks>` for additional information, which can include implementation details, usage notes, or any other relevant context.
- Use `<see langword>` for language-specific keywords like `null`, `true`, `false`, `int`, `bool`, etc.
- Use `<c>` for inline code snippets.
- Use `<example>` for usage examples on how to use the member. Include a `<code>` tag with the language of the example, e.g., `<code language="csharp">`.
- Use `<see cref>` to reference other types or members inline (in a sentence).
- Use `<seealso>` for standalone references to other types or members in the "See also" section of the online docs.
- Use `<inheritdoc/>` to inherit documentation from base classes or interfaces. If there is major behavior change, document the differences.

## Methods

- Use `<param>` to describe method parameters. The description should be a noun phrase that doesn't specify the data type. Begin with an introductory article.
  - If the parameter is a flag enum, start the description with "A bitwise combination of the enumeration values that specifies...".
  - If the parameter is a non-flag enum, start the description with "One of the enumeration values that specifies...".
  - If the parameter is a Boolean, the wording should be of the form "`<see langword="true" />` to ...; otherwise, `<see langword="false" />`.
  - If the parameter is an "out" parameter, the wording should be of the form "When this method returns, contains .... This parameter is treated as uninitialized.".
- Use `<paramref>` to reference parameter names in documentation.
- Use `<typeparam>` to describe type parameters in generic types or methods.
- Use `<typeparamref>` to reference type parameters in documentation.
- Use `<returns>` to describe what the method returns. The description should be a noun phrase that doesn't specify the data type. Begin with an introductory article. If the return type is Boolean, the wording should be of the form "`<see langword="true" />` if ...; otherwise, `<see langword="false" />`.

## Constructors

- The summary wording should be "Initializes a new instance of the <Class> class [or struct].".

## Properties

- The `<summary>` should start with:
  - "Gets or sets..." for a read-write property.
  - "Gets..." for a read-only property.
  - "Gets [or sets] a value that indicates whether..." for properties that return a Boolean value.
- Use `<value>` to describe the value of the property. The description should be a noun phrase that doesn't specify the data type. If the property has a default value, add it in a separate sentence, e.g., "The default is `<see langword="false" />`". If the value type is Boolean, the wording should be of the form "`<see langword="true" />` if ...; otherwise, `<see langword="false" />`. The default is ...".

## Exceptions

- Use `<exception cref>` to document exceptions thrown by constructors, properties, indexers, methods, operators, and events.
- Document all exceptions thrown directly by the member.
- For exceptions thrown by nested members, document only the exceptions users are most likely to encounter.
- The description of the exception describes the condition under which it's thrown. Omit "Thrown if..." or "If..." at the beginning of the sentence. Just state the condition directly, e.g., "An error occurred when accessing a Message Queuing API."

## Instructions
1. Improve structure and clarity
2. Keep all code blocks exactly as-is (verbatim, do not summarize)
3. Add a citation [source: prompts/csharp-docs.prompt.md] at the end
4. Ensure all headings follow a logical hierarchy (no skipping levels)
5. Expand any placeholder text like [user-defined] into helpful descriptions
6. Start with YAML frontmatter including title, description, and tags
7. Do NOT wrap the output in a markdown code block (output raw text)
8. Do not repeat these instructions in your response.

[source: prompts/csharp-docs.prompt.md]