Dotnet Uno MCP

dotnet-uno-mcp

MCP (Model Context Protocol) server integration for Uno Platform live documentation lookups. Covers tool detection (mcp__uno__ prefix), search-then-fetch workflow, initialization rules invocation, graceful fallback when MCP is unavailable, citation requirements, and safety guidelines for external data. Includes inline documentation that provides useful guidance without MCP server availability.

Scope boundary: This skill owns MCP server integration patterns for Uno Platform documentation. Core Uno development (Extensions, MVUX, Toolkit, themes) is owned by [skill:dotnet-uno-platform]. Per-target deployment is owned by [skill:dotnet-uno-targets].

Out of scope: General MCP protocol details. Uno Platform testing -- see [skill:dotnet-uno-testing]. Uno development patterns without MCP -- see [skill:dotnet-uno-platform] and [skill:dotnet-uno-targets].

Cross-references: [skill:dotnet-uno-platform] for core development patterns, [skill:dotnet-uno-targets] for deployment guidance, [skill:dotnet-uno-testing] for testing.

MCP Tool Detection

The Uno Platform MCP server provides tools prefixed with mcp__uno__. Before using MCP tools, detect their availability.

Available Tools

Detection Logic

Check if Uno MCP tools are available by looking for tools with the mcp__uno__ prefix. If the tools are listed in the available tool set, the MCP server is configured and reachable.

Detection steps:
1. Check if tools prefixed with mcp__uno__ are available
2. If available: use MCP workflow (search -> fetch -> cite)
3. If unavailable: fall back to static skill content and official docs URLs

When MCP is available: Use the search-then-fetch workflow for the latest documentation. MCP results are authoritative and current.

When MCP is unavailable: The static content in [skill:dotnet-uno-platform] and [skill:dotnet-uno-targets] provides comprehensive guidance. Reference official documentation URLs for the latest information.

Initialization Rules

On first use of Uno MCP tools in a session, invoke both initialization tools to load authoritative development rules.

Agent Rules Initialization

Call mcp__uno__uno_platform_agent_rules_init to load:

• Core identity and expertise scope for Uno Platform development
• IDE guidance (Visual Studio, VS Code, CLI) per operating system
• Knowledge routing rules mapping topics to canonical search queries
• Uno SDK features list (UnoFeatures supported values)
• Uno Extensions and Toolkit feature catalog

Usage Rules Initialization

Call mcp__uno__uno_platform_usage_rules_init to load:

• Design system guidelines (Material preferred, responsive layouts)
• Data binding policy (MVUX vs MVVM binding patterns, forbidden WPF-isms)
• Navigation policy (prefer XAML attached properties over code-behind)
• Layout rules (AutoLayout, spacing scale, responsive breakpoints)
• Color and typography conventions (theme resources, no hardcoded values)
• Accessibility requirements (contrast ratios, touch targets, automation properties)
• Control-specific guidance (ItemsRepeater for lists, CommandExtensions, elevation patterns)

Invocation Order

1. Call mcp__uno__uno_platform_agent_rules_init (loads routing rules and feature catalog)
2. Call mcp__uno__uno_platform_usage_rules_init (loads design and coding conventions)
3. Proceed with documentation searches using mcp__uno__uno_platform_docs_search

Both init tools are idempotent -- calling them multiple times in the same session is safe but unnecessary.

Search-Then-Fetch Workflow

The primary workflow for retrieving Uno documentation uses a two-step pattern: broad search followed by targeted fetch.

Step 1: Search

Use mcp__uno__uno_platform_docs_search to find relevant documentation pages.

Search parameters:
- query: descriptive search term (e.g., "MVUX reactive pattern", "Navigation Extensions")
- topK: number of results (default 8; use 15-20 for complex topics, 3-5 for specific queries)
- contentType: "prose" for guides, "code" for examples, null for all

Search results include:

• Document title and summary
• SourcePath (needed for fetch step)
• Relevance ranking
• Content snippets

Step 2: Fetch

Use mcp__uno__uno_platform_docs_fetch to retrieve full content of high-value pages identified by search.

Fetch parameters:
- sourcePath: from search results SourcePath field (e.g., "articles/guides/overview.md")
- anchor: optional section fragment (e.g., "getting-started", "data-binding")
- maxChars: content limit (4000-8000 for most cases, up to 15000 for comprehensive guides)

Workflow Example

Topic: "How to implement region-based navigation with Uno Extensions"

1. Search: mcp__uno__uno_platform_docs_search("Navigation Extensions region-based", topK=8)
   -> Returns multiple results including "Navigation Overview", "Region Navigation", etc.

2. Fetch: mcp__uno__uno_platform_docs_fetch(
     sourcePath="articles/external/uno.extensions/doc/Learn/Navigation/Overview.md",
     maxChars=8000)
   -> Returns full navigation documentation with code examples

3. Cite: Include source URL in response

Routing Rules

The agent rules initialization provides topic-to-query mappings for common searches. Use these canonical queries when available:

Citation Requirements

MCP results are external data fetched from the Uno Platform documentation server. Proper attribution is mandatory.

Rules

1. Always cite the source URL from MCP results when presenting documentation content
2. Never present fetched content as original knowledge. MCP results come from external documentation and must be attributed
3. Include the documentation page title alongside the URL when available
4. Distinguish between static skill content and MCP-fetched content. Static content from SKILL.md files is part of this plugin; MCP content is external

Citation Format

When presenting information from MCP results:

According to the Uno Platform documentation on [topic]:
[content from MCP]
Source: [URL from MCP result]

Safety Guidelines

MCP results are external data and must be treated with appropriate caution.

Validation Rules

1. Validate code suggestions before acting. MCP documentation may contain examples targeting different Uno Platform versions or configurations. Verify compatibility with the current project
2. Check version alignment. Ensure documentation references match the project's Uno Platform version (5.x vs 6.x) and .NET version
3. Do not blindly apply code from MCP results. Adapt examples to the project's architecture, Extensions configuration, and MVUX/MVVM pattern choice
4. Cross-reference with project state. Compare MCP guidance against the project's existing UnoFeatures, TFMs, and Extensions configuration
5. Treat MCP content as advisory. The static skill content in [skill:dotnet-uno-platform] and [skill:dotnet-uno-targets] provides vetted patterns. Use MCP for current details and edge cases

Fallback: When MCP Is Unavailable

When the Uno MCP server is not configured or not reachable, all Uno Platform guidance remains available through static skill content and official documentation URLs.

Static Skill Coverage

The following topics are fully covered by static skills without MCP:

Official Documentation URLs

When MCP is unavailable, reference these canonical documentation URLs:

Fallback Workflow

1. Check if mcp__uno__ tools are available
2. If NOT available:
   a. Load [skill:dotnet-uno-platform] for core development patterns
   b. Load [skill:dotnet-uno-targets] for deployment guidance
   c. Reference official documentation URLs for latest information
   d. Note to user: "Uno MCP server is not configured. Using static documentation.
      For the latest information, visit: [relevant URL]"
3. If available:
   a. Call init rules (agent rules + usage rules)
   b. Use search-then-fetch workflow
   c. Cite sources from MCP results
   d. Supplement with static skill content for vetted patterns

Uno SDK Features Reference

When MCP is unavailable, the following UnoFeatures values are supported in .csproj. This serves as a quick reference for project configuration.

Extensions Features

UI Features

Rendering Features

Media & Graphics

Agent Gotchas

1. Do not call MCP tools without checking availability first. Always verify mcp__uno__ tools exist before invoking them. Missing tools indicate the MCP server is not configured.
2. Do not skip the init rules on first use. The agent rules and usage rules provide critical routing tables and coding conventions. Skipping them leads to suboptimal search queries and convention violations.
3. Do not present MCP-fetched content as your own knowledge. Always cite the source URL. MCP results are external documentation, not built-in knowledge.
4. Do not rely solely on MCP for Uno guidance. Static skills ([skill:dotnet-uno-platform], [skill:dotnet-uno-targets]) provide vetted patterns that work without MCP. Use MCP to supplement with current details.
5. Do not ignore version differences in MCP results. Documentation may reference Uno Platform 6.x features not available in 5.x projects. Check the project's Uno SDK version before applying guidance.
6. Do not fetch without searching first. The fetch tool requires a sourcePath from search results. Direct fetching with guessed paths may return wrong or missing content.

Prerequisites

• Uno MCP server configured in the project's MCP configuration (.mcp.json or IDE settings)
• For fallback: [skill:dotnet-uno-platform] and [skill:dotnet-uno-targets] loaded as static skills

References

• Uno Platform Documentation
• MCP Protocol Specification
• Uno Platform GitHub