Understand a new codebase quickly
Maps an unfamiliar repository: architecture, key flows, conventions, and where to start.
The prompt
Help me understand this codebase. I've just joined the project.
What I can share: [file tree, README, key files, package/dependency files — paste]
My role and first task: [ROLE / TASK]
Produce an onboarding guide:
1. What the system does and who uses it.
2. Architecture — main components, how they talk to each other, data flow (include a Mermaid diagram).
3. Tech stack and key dependencies.
4. Directory map — what lives where and why.
5. Key flows — trace 2–3 important requests or jobs end to end through the code.
6. Conventions — naming, patterns, testing, config, environment setup.
7. Risky areas — complex, fragile, or poorly tested parts.
8. Where to start for my task and the files I'll probably touch.
Only state what the code shows; mark guesses as [INFERRED].
Highlighted [brackets] are blanks to replace with your own details.
Fill in the blanks and use this promptMore Software Development prompts
What to fill in
- ROLE / TASK
- INFERRED
How this prompt is built
This prompt follows the RTF structure (Role, Task, Format). RTF tells the model who to be, what to do and what shape the answer should take. It is the quickest structure that still gives noticeably better results than a bare request.
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