Design OS

One-Shot Implementation

Build your entire product in a single session for simpler projects.

For simpler products or when you want to build everything in one session, this approach lets your agent plan and implement the entire product at once.

How It Works

  1. Open product-plan/prompts/one-shot-prompt.md
  2. Add any additional notes (tech stack preferences, constraints)
  3. Deliver the prompt to your coding agent in Plan mode
  4. Answer the agent's clarifying questions about auth, user modeling, etc.
  5. Give the go-ahead and let the agent implement everything

Why Plan Mode?

Plan mode encourages the agent to analyze the instructions thoroughly, ask clarifying questions, and build a complete implementation plan before writing code. This catches issues early and ensures the plan works for your codebase.

The prompt references product-overview.md and instructions/one-shot-instructions.md, and guides your agent to ask important questions before starting.

Clarifying Questions

The prompt includes questions about:

  • Authentication & authorization — Login methods, user roles
  • User & account modeling — Single-user vs multi-user, teams/workspaces
  • Tech stack preferences — Backend framework, database
  • Any other clarifications — Project-specific requirements

When to Use One-Shot

  • Smaller products — Few sections, straightforward features
  • Prototypes — Quick builds where iteration happens later
  • Familiar patterns — When you know exactly what you want
  • Time constraints — When you need something built fast

Tips for One-Shot Success

  • Answer all questions first — Don't let the agent start until clarifying questions are resolved
  • Review the plan — Ask to see the implementation plan before coding begins
  • Test incrementally — Even in one-shot mode, test as sections are completed

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