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