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Datfx Labs Claude Guide

Codebase Exploration

You have just cloned a repository you have never seen before. Or you are returning to a project you have not touched in six months. Either way, the fastest path to productive work is the same: start broad, then narrow.

Claude can read and cross-reference your entire codebase in seconds. The prompts below guide that process from first impression to deep understanding.

Getting Oriented in a New Repo

Start with the widest possible view, then drill into what matters to your task.

give me an overview of this codebase
explain the main architecture patterns used here
what are the key data models?
how is authentication handled?

Each answer reveals the next question. After the overview you might ask about a specific service. After the architecture explanation you might ask how two components interact. Claude retains context across the conversation — you are not starting over each time.

Tip: Use the project’s own domain language. If the codebase calls them “listings” not “products”, ask about listings. Claude picks up vocabulary from the code and responds in kind.

Finding Specific Code

Once you know the shape of the project, locate the code you actually need to work with.

find the files that handle user authentication
how do these authentication files work together?
trace the login process from front-end to database

The third prompt is the most powerful. “Trace X from A to B” asks Claude to follow the execution path across multiple files — request handling, middleware, business logic, database queries — and explain each step. This is faster than reading five files yourself and connecting the dots.

graph TD A[Start broad] --> B[Overview + architecture] B --> C[Narrow to a domain] C --> D[Find relevant files] D --> E[Trace execution flow] E --> F[Ready to make changes] style A fill:#1e293b,color:#7dd3fc,stroke:#334155 style B fill:#1e293b,color:#a5b4fc,stroke:#334155 style C fill:#1e293b,color:#a5b4fc,stroke:#334155 style D fill:#1e293b,color:#a5b4fc,stroke:#334155 style E fill:#1e293b,color:#a5b4fc,stroke:#334155 style F fill:#1e293b,color:#86efac,stroke:#334155

Understanding Before Changing

The most expensive mistakes in a new codebase come from changing something without understanding what depends on it. Before any significant edit, invest a prompt in understanding.

before making any changes, explain how the payment module works
what would break if I changed the UserService interface?
what other parts of the codebase depend on this function?

These prompts are free — Claude only reads, it does not edit. The cost of a few seconds of context-gathering is almost always less than the cost of tracking down an unexpected breakage.

Code Intelligence Plugins

By default, Claude finds code through text search — it looks for file and function names, follows imports, reads related files. This works well for most projects.

For large or complex codebases, installing a language-specific code intelligence plugin gives Claude a more precise navigation layer: actual “go to definition” and “find references” capabilities, not pattern matching. When Claude says “this function is called in three places”, with a plugin it knows exactly where those three calls are.

Check Plugins for available language plugins. They are most valuable when working with large TypeScript/JavaScript, Python, Go, or Java projects where import chains are deep.

Prompts for Specific Situations

You inherited legacy code:

what parts of this codebase are the oldest or most technical-debt-heavy?
what would you prioritize refactoring first, and why?

You are adding a feature and need to find the right place:

I want to add email notifications when an order ships.
Where in the codebase would this logic go?
What existing patterns should I follow?

You want to understand test coverage:

what parts of the payment module are not covered by tests?

You are reviewing someone else’s PR:

explain what this PR does and what the risk areas are

Next: Once you know the codebase, Debugging patterns help you fix issues efficiently. Prompting Patterns covers @file references for including specific files in your exploration prompts.