Guides the agent in writing and organizing solution-level Markdown documentation for .NET projects, compatible with GitBook, DocFX, GitHub Pages, and similar platforms. Use this skill when creating or improving README files, how-to guides, architecture docs, changelogs, or multi-page documentation sites for a solution. Architecture and API documentation sections are optional and must be confirmed with the user before generating them. Documentation must always be updated when existing features change or new features are introduced.
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Guides the agent in writing and organizing solution-level Markdown documentation for .NET projects, compatible with GitBook, DocFX, GitHub Pages, and similar platforms. Use this skill when creating or improving README files, how-to guides, architecture docs, changelogs, or multi-page documentation sites for a solution. Architecture and API documentation sections are optional and must be confirmed with the user before generating them. Documentation must always be updated when existing features change or new features are introduced.
This skill helps agents plan, write, organize, and keep current Markdown-based documentation for .NET solutions. It covers the core documentation structure—from the root README.md down to how-to guide pages, changelogs, and contribution guides—so that the output is useful both as standalone repository documentation and as a rendered site on GitBook, DocFX, GitHub Pages, or compatible platforms. Architecture and API documentation sections are optional: the agent must ask the user whether each is needed before generating them. Documentation is treated as a living artifact: it must be updated as part of every task that introduces or changes a feature.
When to Use
Creating or restructuring a docs/ folder for a .NET solution
Writing or improving the root README.md and per-project README.md files
Building a GitBook-compatible documentation site (SUMMARY.md, chapter pages)
Writing how-to guides and topic pages placed directly in the docs root
Writing a CHANGELOG.md following Keep a Changelog conventions when the user requests it
Adding CONTRIBUTING.md, CODE_OF_CONDUCT.md, or SECURITY.md
Writing architecture documentation or ADRs when the user explicitly requests them
Producing an API overview when the user confirms it is needed and the target platform supports it
Updating guide pages, README files, and the CHANGELOG when an existing feature changes
Adding new topic pages or extending existing ones when a new feature is introduced
When Not to Use
Writing XML documentation comments inside C# source code (use the xml-comments-doc skill instead)
Configuring DocFX or MkDocs pipelines and build tooling
Writing prose content for non-.NET or non-developer audiences without a solution context
Generating API reference pages from XML comments (use DocFX or similar tooling for that)
Inputs
Input
Required
Description
Solution name and purpose
Yes
The name of the .NET solution and what it does
Project list
Yes
The projects or libraries in the solution and their roles
Target platform
No
GitBook, DocFX, GitHub Pages, or other — affects structure and front matter
Audience
No
Library consumers, internal developers, or end users
Existing docs
No
Any current documentation to review, improve, or restructure
Include architecture docs
No
Whether to generate an architecture/ section — must be confirmed with the user
Include API docs
No
Whether to generate an api/ section — must be confirmed with the user
Include CHANGELOG
No
Whether to generate and maintain a CHANGELOG.md — must be confirmed with the user
Nature of change
No
For update tasks: whether the task adds a new feature, changes an existing one, or removes/deprecates one
Changelog history
No
Version history or release notes to incorporate
Workflow
Step 1: Understand the solution and its documentation goals
Before writing, clarify:
What the solution does and who its primary audience is
Whether the documentation will be published on a platform (GitBook, GitHub Pages) or consumed directly in the repository
Which parts of the documentation already exist and what needs to be created or improved
Whether the solution is a library (needs API reference guidance), an application (needs operational docs), or a framework (needs both)
Step 2: Ask about optional sections
Before generating any documentation, explicitly ask the user:
Architecture documentation: "Do you want an architecture/ section with an overview page and support for Architecture Decision Records (ADRs)?" — Do not generate architecture/ unless the user confirms.
API documentation: "Do you want an api/ section with per-library overview pages?" — Explain that this section can be large and depends on the target platform. Do not generate api/ unless the user confirms.
Changelog: "Do you want a CHANGELOG.md to track notable changes over time?" — Do not generate or maintain CHANGELOG.md unless the user confirms.
If the user's original request already provides a clear answer to any question (e.g., "create an architecture overview", "add a changelog entry"), treat that as confirmation and skip asking for that item.
Step 3: Define the documentation structure
Use this baseline structure for a .NET solution:
docs/
README.md # Introduction and navigation entry point
SUMMARY.md # GitBook table of contents (if using GitBook)
getting-started.md # Quick-start guide
<topic>.md # Simple topic page (one page is enough)
<complex-topic>/ # Subfolder for topics that span multiple pages
README.md # Overview / entry point for the topic
<subtopic>.md # Individual sub-pages
contributing.md # Or CONTRIBUTING.md at repository root
architecture/ # ONLY if confirmed by the user
overview.md # High-level architecture diagram and description
decisions/ # Architecture Decision Records (ADRs)
adr-0001-*.md
api/ # ONLY if confirmed by the user — always placed last
overview.md # API surface description and usage patterns
<project-name>.md # Per-library API overview (one file per main library)
CHANGELOG.md is optional. When present (user confirmed), place it at the repository root. It does not belong inside docs/.
Key layout rules:
Simple topics (single-page coverage) are placed as individual .md files directly at the docs/ root. Name them by subject (e.g., authentication.md, configuration.md).
Complex topics (multiple related pages) get their own subfolder directly under docs/, named after the topic (e.g., multi-tenancy/, payments/). Each such subfolder must contain a README.md that serves as the entry point and links to all sub-pages within it.
architecture/ is included only when the user has confirmed it is needed (Step 2).
api/ is included only when the user has confirmed it is needed (Step 2). When present, it is always placed at the end of the docs folder, after all other sections.
Adapt the structure based on the platform:
GitBook: Requires SUMMARY.md at the docs root with a hierarchical table of contents. Every page linked in SUMMARY.md must exist. Use relative links between pages.
DocFX: Requires toc.yml files in each folder and a docfx.json configuration. Front matter (uid:, title:) should follow DocFX conventions.
GitHub Pages / plain Markdown: No special structure required; ensure all internal links use relative paths and resolve correctly from the repository root.
Step 4: Write the root README.md
The root README.md is the single entry point that gives any reader — in seconds — a clear picture of what the project does, how to start, and where to learn more. It must be brief: no exhaustive API tours, no lengthy configuration walkthroughs. All detail lives in docs/.
The root README.md must contain exactly these sections, in order:
Project name and one-line description (heading + tagline)
Badges (build status, NuGet version, license, coverage — as applicable)
Summary: Two to four sentences — what the solution is, what problem it solves, and who it is for. Nothing more.
Packages — see rules below
Usage: Two to four short, self-contained code snippets covering only the most common scenarios. Each snippet must:
Be complete enough to copy-paste and run
Cover a distinct major use case (e.g., creating a payment, handling a webhook)
Be followed by a one-line explanation of what it demonstrates
End with "→ See topic page for full details." linking to the relevant documentation page
Not exceed 20 lines per snippet; if it would, it is too detailed for the README
Installation: NuGet package names with dotnet add package commands (≤ 3 packages) or a pointer to the Packages section (> 3 packages)
Documentation: A short list of links into docs/ — getting-started guide, and two or three key topic pages. Do not reproduce the full SUMMARY.md here.
License and contributing links
What does not belong in the root README:
Step-by-step configuration guides
Full API reference or method listings
More than four usage snippets
Content that already lives in a docs/ topic page
Packages section rules
Up to 3 packages — list them inline in the Installation section with dotnet add package commands and a single NuGet version badge per package. Do not create a separate Packages section.
More than 3 packages — create a dedicated ## Packages section before the Installation section. For each package:
Give the package name as a sub-heading or bold label
Write a one-sentence description of what it does and who should reference it
Render a NuGet version badge that links to the package's NuGet.org page, using the Shields.io NuGet badge format:
Multi-page topic — create a dedicated subfolder directly under docs/, named after the topic. The subfolder must contain a README.md that introduces the topic and links to every sub-page within it:
docs/
multi-tenancy/
README.md # Introduction and links to sub-pages
configuration.md
data-isolation.md
tenant-resolution.md
payments/
README.md
getting-started.md
webhooks.md
error-handling.md
Decision criteria — use a subfolder when any of the following is true:
The topic requires more than one page to cover completely
The topic has distinct subtopics that readers navigate independently
The topic is complex enough that a flat page would exceed ~400 lines
Each guide page (whether flat or inside a subfolder) should:
State what the reader will accomplish in a single sentence
List prerequisites (packages, configuration, or concepts to know first)
Walk through the scenario step by step with code examples
End with a pointer to related pages or the API docs (if present)
Each subfolder README.md should additionally:
Summarize the topic in one paragraph
Link to every sub-page with a one-line description of each
Step 7: Write the architecture section (only if confirmed in Step 2)
docs/architecture/overview.md should cover:
The major layers or components and their responsibilities
How components interact (data flow, dependency direction)
Key technology and framework choices with brief rationale
A textual or Mermaid diagram of the solution structure
Use Mermaid diagrams (```mermaid) for architecture diagrams since they render natively on GitHub, GitBook, and DocFX with the right plugins.
Use the lightweight ADR format for significant design decisions:
# ADR-NNNN: <ShortTitle>## Status
Accepted | Proposed | Superseded by ADR-XXXX
## Context<Whatsituationorproblemmotivatedthisdecision?>## Decision<Whatwasdecidedandwhy?>## Consequences<Whataretheimplications — positiveandnegative — ofthisdecision?>
Number ADRs sequentially (adr-0001-use-kista.md). ADRs are never deleted; superseded ones are marked with a status update.
Step 8: Write the API section (only if confirmed in Step 2)
The api/ folder is always placed at the end of the docs/ folder, after all other sections. Its scope and depth depend on the target platform:
GitBook / GitHub Pages: Write narrative overview pages per library — describe the main types, entry points, and common usage patterns. Keep pages focused; do not replicate every method signature.
DocFX: API reference pages are typically auto-generated from XML comments. Use the api/ folder only for hand-written conceptual overview pages that DocFX cannot generate automatically.
Each page should:
Describe the library's public surface in one paragraph
Show the most important types and how they are typically composed
Link to the getting-started guide and relevant how-to pages
Step 9: Write the CHANGELOG (only if confirmed in Step 2)
CHANGELOG.md is optional. Do not create or update it unless the user has confirmed they want one (Step 2), or the user explicitly references it in their request.
# Changelog
All notable changes to this project will be documented in this file.
## [Unreleased]## [X.Y.Z] - YYYY-MM-DD### Added### Changed### Deprecated### Removed### Fixed### Security
Place CHANGELOG.md at the repository root, not inside docs/. For multi-package solutions, keep one changelog per independently versioned package.
Step 10: Write the getting-started guide
docs/getting-started.md must be runnable from start to a visible result:
Prerequisites (SDK version, tools, environment)
Installation or project setup steps
Minimal working example with expected output
Pointer to the next how-to page or API docs (if present)
Step 11: Write the GitBook SUMMARY.md (if targeting GitBook)
SUMMARY.md is the authoritative table of contents for GitBook. Every page that should appear in navigation must be listed. Place topic pages and topic subfolders before architecture/ and api/; those optional sections always come last:
If a CHANGELOG.md exists (user-confirmed), link it from SUMMARY.md after topic pages and before optional sections: * [Changelog](../CHANGELOG.md). Because CHANGELOG.md lives at the repository root, the path from docs/SUMMARY.md must go up one level.
Rules for SUMMARY.md:
Use relative paths from the docs root
Indent child pages with two spaces
Every listed file must exist; broken links cause GitBook to fail
Do not nest more than three levels deep
Single-page topics appear as flat entries; multi-page topic subfolders appear as a parent entry pointing to the subfolder README.md, with sub-pages indented beneath
CHANGELOG.md is linked only when the user has confirmed it should exist; use ../CHANGELOG.md because it lives at the repository root
architecture/ and api/ are listed only when the user has confirmed they are needed
api/ always appears after architecture/ when both are present
Step 12: Keep documentation in sync with code changes
Documentation must be updated as part of the same task that introduces or modifies a feature — never deferred to a follow-up task. Apply this step whenever the work involves a code change rather than writing docs from scratch.
Identify affected documentation
Before writing or modifying any doc page, scan the existing docs/ folder and identify:
Every guide page or subfolder that describes, references, or provides examples for the changed or new feature
Whether the root README.md features list needs to be updated (significant new or removed capability)
Whether the getting-started guide uses the changed feature in its example
For a changed feature
Update every affected guide page: correct instructions, code examples, configuration snippets, and any behavior description that is no longer accurate.
If the change is breaking or alters observable behavior, add a short callout or note near the top of the affected page.
If a CHANGELOG.md exists, add a ### Changed entry under [Unreleased].
For a new feature
Decide where it belongs using the single-page vs. multi-page rule from Step 6:
Simple feature → new flat .md file at the docs/ root, or a new section appended to an existing closely related page.
Complex feature with multiple subtopics → new topic subfolder under docs/ with a README.md entry point.
Write the new page(s) following the guide-page format.
Add the new page or subfolder to SUMMARY.md (if using GitBook) in the correct position — before architecture/ and api/.
Update the root README.md usage section if the new feature is significant enough to warrant a snippet there.
If a CHANGELOG.md exists, add a ### Added entry under [Unreleased].
For a deprecated or removed feature
If deprecated: mark the relevant guide content with a deprecation notice and link to the replacement feature's documentation.
If removed: delete or archive the guide page(s), remove the entries from SUMMARY.md, and update any cross-links from other pages that pointed to the removed content.
If a CHANGELOG.md exists, add a ### Deprecated or ### Removed entry under [Unreleased].
Rules
A code change and its documentation update must land in the same commit or pull request.
If no docs/ folder exists yet when a feature change is requested, create it following the baseline structure from Step 3 before documenting the feature.
When adding a new page, always verify the SUMMARY.md is updated so the page is reachable in navigation.
Step 13: Validate cross-links and structure
Before finishing:
Verify all internal Markdown links resolve to existing files using relative paths
Confirm SUMMARY.md (if present) lists every page that should be navigable, including any newly added pages
Check that no page is orphaned (exists in the folder but not linked from any navigation or parent page)
Confirm that simple single-page topics are flat files at the docs/ root
Confirm that every multi-page topic has a dedicated subfolder with a README.md entry point
Confirm there is no generic guides/ subfolder — topic subfolders are named after their subject
Confirm that api/ (if present) is the last section in both the folder and in SUMMARY.md
Confirm that architecture/ (if present) was explicitly requested by the user
Confirm that CHANGELOG.md (if present) was explicitly requested by the user and is not inside docs/
Confirm that every code change in this task has a corresponding doc update
If a CHANGELOG.md exists, confirm it has an entry for every feature change or addition in this task
Validate Mermaid diagrams render correctly by checking syntax
Ensure heading hierarchy is consistent (one # per page, ## for sections, ### for subsections)
Validation
Root README.md is brief: summary (2-4 sentences), usage snippets (2-4 major cases only), installation, and documentation links
Each usage snippet covers a distinct major use case, is ≤ 20 lines, and ends with a link to the relevant docs/ page
The root README does not contain step-by-step guides, full API listings, or content that belongs in docs/
Solutions with more than 3 packages have a dedicated ## Packages section with NuGet badges and one-sentence descriptions
Solutions with 3 or fewer packages list them inline in the Installation section without a separate Packages section
NuGet badges use the Shields.io format and link to the correct NuGet.org package page
If architecture pages exist for individual packages, the Packages table links to them
docs/ folder is present and follows the agreed structure
SUMMARY.md exists and lists all navigable pages (GitBook targets only)
Simple single-page topics are placed as flat .md files at the docs/ root
Complex multi-page topics have a dedicated subfolder under docs/ named after the topic
Every topic subfolder contains a README.md that introduces the topic and links to its sub-pages
There is no generic guides/ subfolder — subfolders are named by topic
The user was asked before generating architecture/ — the folder exists only if confirmed
The user was asked before generating api/ — the folder exists only if confirmed
The user was asked before generating CHANGELOG.md — the file exists only if confirmed
When CHANGELOG.md is present, it is at the repository root (not inside docs/) and follows Keep a Changelog conventions
When api/ is present, it appears at the end of the docs folder and after architecture/
All internal Markdown links use relative paths and resolve to existing files
ADRs (if present) are numbered sequentially and use the standard status/context/decision/consequences format
Every feature change or addition in this task has a corresponding doc update
If CHANGELOG.md is present, every feature change or addition has an entry under [Unreleased]
Newly added pages are listed in SUMMARY.md and are reachable from navigation
Removed or deprecated features have their documentation marked or removed accordingly
No page is orphaned (all files are reachable from the navigation structure)
Mermaid diagrams use valid syntax
Heading hierarchy is consistent throughout all pages (single # title per page)
Per-project README.md files exist for significant libraries or applications
Platform-specific requirements (DocFX toc.yml, GitBook SUMMARY.md) are met
Common Pitfalls
Pitfall
Solution
Root README.md is too long and mixes guide content
The README must contain only: summary, usage snippets for major cases, packages, installation, and doc links — all detail goes into docs/
Usage section has too many snippets
Limit to 2-4 snippets covering only the most common scenarios; edge cases and advanced usage belong in guide pages
Usage snippet exceeds 20 lines
The snippet is too complex for the README; move the full example to a guide page and link to it
Usage snippet has no link to docs
Every snippet must end with a "→ See topic for full details." reference
README duplicates content already in docs/
Remove duplicated content from the README and replace it with a link to the relevant doc page
More than 3 packages but no dedicated Packages section
Create a ## Packages table with NuGet badges and one-sentence descriptions when the solution has more than 3 packages
NuGet badge URL uses the wrong format or links to a search page
Use https://img.shields.io/nuget/v/<PackageId>.svg linking to https://www.nuget.org/packages/<PackageId>
Package descriptions in the Packages table are more than one sentence
Keep each description to one sentence; deeper content belongs in per-project READMEs or guide pages
Architecture link in Packages table missing when architecture page exists
When architecture/ contains a page for a package, add [Architecture](<relative-path>) to that package's Description cell
Packages section created for 3 or fewer packages
Only create the section when there are more than 3 packages; otherwise list them inline in Installation
A complex topic with many pages is placed as a single flat file
Split it into a subfolder named after the topic, with a README.md entry point and one file per sub-page
A topic subfolder has no README.md
Every topic subfolder must have a README.md that introduces the topic and links to its sub-pages
A generic guides/ subfolder is created
Name subfolders after their topic, not after a generic category; guides/ adds no useful grouping
Architecture section is created without asking the user
Always confirm with the user before generating architecture/ — it may not be needed
API section is created without asking the user
Always confirm with the user and the target platform before generating api/ — it can be large and platform-specific
api/ folder appears in the middle of the docs structure
Place api/ last in the folder and last in SUMMARY.md, after all other sections
Feature changed but documentation not updated
Apply Step 12: scan all affected pages and update them as part of the same task
New feature added but no new or updated doc page was written
Every new feature must have at least one guide page; apply the single-page vs. subfolder rule
Feature removed but old guide pages remain
Delete or archive orphaned pages and remove them from SUMMARY.md
CHANGELOG created without user confirmation
CHANGELOG.md is optional — only create it when the user explicitly requests it
CHANGELOG placed inside docs/
CHANGELOG.md belongs at the repository root, not inside the docs/ folder
CHANGELOG not updated after a feature change
When CHANGELOG.md exists, every Added, Changed, Deprecated, or Removed item must have an entry under [Unreleased]
New page added but not listed in SUMMARY.md
Always update SUMMARY.md when adding a new page; orphaned pages are not navigable on GitBook
Documentation update is deferred to a later task
Docs and code changes must land together — deferring produces stale documentation
GitBook SUMMARY.md references files that don't exist
Create all listed files before publishing; GitBook fails on missing links
Topic subfolder README.md is missing from SUMMARY.md
Use the subfolder README.md as the parent entry; list sub-pages indented beneath it
Internal links use absolute paths or GitHub UI URLs
Always use relative paths: ../multi-tenancy/configuration.md not full GitHub URLs
ADRs are updated in-place after acceptance
Add a new ADR and mark the old one as superseded; never rewrite history
Architecture diagram is a static image instead of Mermaid
Use Mermaid so diagrams stay in sync with code and render on all platforms
CHANGELOG entries are added to old versions instead of [Unreleased]
Always add new changes under [Unreleased] and promote on release
DocFX pages lack uid: front matter
Add uid: and title: front matter to every DocFX page for xref support
Per-project READMEs duplicate the root README
Focus per-project docs on what is unique to that project; link to the root for shared content
Pages exist in docs/ but are not linked from SUMMARY.md
Treat the navigation file as the source of truth; prune or link orphaned files
Mermaid diagram uses unsupported features for the target platform
Test diagrams on the target rendering environment (GitBook, GitHub, DocFX) before committing
