AI Agent Spec Builder
A free, browser-based tool. Runs entirely in your browser — no sign up, nothing stored.
Agent spec
Your prompt
Copy-ready prompt
A template built from your inputs — paste it into your AI tool. Runs in your browser; nothing is uploaded.
How to use this calculator
- State the agent's goal and list the tools/APIs it can use.
- Add constraints and success criteria.
- Copy the prompt to generate the agent's planning spec.
How it works
The prompt asks for a deterministic, safe plan — the agent's role, a step-by-step sequence with the tool used at each step, guardrails and failure handling, and how to verify success — and to ask for missing info rather than assume.
It builds the planning prompt; it does not run an agent or write code.
Frequently asked questions
Does this use AI or send my prompt anywhere?
No. It runs entirely in your browser using rule-based checks — your prompt is never uploaded or sent to any AI model. Still, avoid pasting passwords, API keys or private data into any tool.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.



