Skill: docs-lookup

Verify API accuracy using documentation tools before writing code.

Purpose

Prevent incorrect API usage by verifying method signatures, parameters, and patterns against official documentation before implementation. Never guess an API -- look it up.

Why This Matters

•Incorrect APIs waste iterations on build errors
•Deprecated APIs create tech debt from the start
•Wrong method signatures cause runtime failures the tests catch too late
•A 30-second lookup saves a 5-minute failed iteration

Verification Tools (Use in Order of Preference)

1. Web Search

Best for: Latest docs, community solutions, release notes, breaking changes.

code

Search: "[library name] [method/class] documentation [year]"
Search: "[library name] migration guide v[old] to v[new]"

2. WebFetch

Best for: Reading specific documentation pages you already know the URL for.

code

Fetch: https://learn.microsoft.com/en-us/dotnet/api/[namespace.class]
Fetch: https://docs.python.org/3/library/[module].html

3. Context7 MCP Server

Best for: Third-party library documentation with version awareness.

code

Query: "How to use [library] [feature] in version [X]"

4. Microsoft Learn MCP Server

Best for: Microsoft technologies (.NET, Azure, C#, ASP.NET, etc.)

code

Search: "[API name] [method]"
Code Samples: "[feature] example code"
Full Reference: Fetch full API page with overloads

Mandatory Verification Workflow

Before using any API in implementation:

code

1. IDENTIFY what you need
   └─> Class name, method, expected behavior

2. SEARCH documentation
   └─> Use the most appropriate tool above

3. VERIFY the API exists
   └─> Check method signature, parameters, return type

4. CHECK for deprecation
   └─> Look for "Obsolete", "Deprecated", "Use X instead"

5. FIND a working example
   └─> Code samples are more reliable than guessing

6. IMPLEMENT with confidence
   └─> Now write the code

When to Verify

•Always: First time using any library or API method
•Always: After encountering a build error related to APIs
•Always: When compiler warnings mention deprecation
•Always: When uncertain about parameter types or order
•Always: When migrating to a new version of a library

Common Verification Scenarios

Scenario	What to Look Up
Using a new NuGet package	Package README, API reference
Calling an external REST API	Endpoint URL, auth method, request/response schema
Using a framework feature	Official docs for correct setup pattern
Handling specific error types	Exception hierarchy, what throws what
Configuring middleware	Correct order, options, and method names
Writing tests with a framework	Test base class, assertions, setup patterns

Anti-Patterns

•Guessing method names based on what seems logical
•Assuming parameters match a similar method in another library
•Using Stack Overflow answers from 3+ years ago without checking version
•Ignoring IntelliSense warnings about deprecated members
•Copying patterns from one version and assuming they work in another