Promptimal
Promptimal is a free, MIT-licensed, open-source Linux command-line tool for improving AI prompts without a dataset.
What Promptimal is
Promptimal is a free, MIT-licensed, open-source Linux command-line tool for improving AI prompts without a dataset. It uses a genetic algorithm to refine a prompt according to an improvement description. You can enter the prompt and goal interactively in a terminal or pass both as command-line arguments, then watch progress in a terminal interface. By default, an LLM scores candidate prompts with a self-consistency method. You can replace that evaluator with a Python function that accepts a prompt and returns a score from 0 to 1. Command-line settings control iterations, candidates per iteration, and the stopping threshold, whose default is 1.0. Install it with `pipx install promptimal`, then place an OpenAI API key in the environment. The documented current setup uses OpenAI; Anthropic, Groq, and Ollama support are listed as roadmap items.
Good
- Free and MIT licensed
- No dataset required
- Configurable optimization controls
- Custom Python evaluators supported
- Terminal progress interface
Watch out
- Linux is the listed platform
- OpenAI API key required
- Other providers are roadmap items
- No team collaboration
Who it suits
Promptimal suits Linux users who want automated prompt optimization from a terminal. It is intended for people comfortable configuring an OpenAI API key and, optionally, a Python evaluator.
Verdict
Promptimal offers configurable, automated prompt refinement in a lightweight terminal workflow. Its current provider documentation centers on OpenAI, so users seeking other providers must note their roadmap status.
The facts
Each one read from Promptimal's own pages, with the date it was checked.
What it does
- API requirement
- The README says to add an OpenAI API key to the environment before using Promptimal.checked 9 Oct 2026
- Configuration
- The number of iterations, candidate samples per iteration, and score threshold can be configured from the command line.checked 9 Oct 2026
- Current integrations
- The README documents OpenAI API key configuration and does not describe other current provider integrations.checked 9 Oct 2026
- Custom evaluators
- Users can supply a Python evaluator that accepts a prompt and returns a score between 0 and 1.checked 9 Oct 2026
- Default threshold
- The README says the default stopping threshold is 1.0.checked 9 Oct 2026
- Evaluation
- By default, an LLM evaluates candidate prompts using a self-consistency approach.checked 9 Oct 2026
- How to install
- The README gives `pipx install promptimal` as the installation command.checked 9 Oct 2026
- How to start
- Users can launch Promptimal in a terminal and enter a prompt and an improvement description, or provide them as command-line arguments.checked 9 Oct 2026
- Installation
- The README gives `pipx install promptimal` as the installation command.checked 9 Oct 2026
- License
- The GitHub repository identifies the project as MIT licensed.checked 9 Oct 2026
- OpenAI setup
- The README instructs users to set an OpenAI API key in their environment before running Promptimal.checked 9 Oct 2026
- Optimization
- It uses a genetic algorithm to iteratively refine a prompt based on a description of what the user wants to improve.checked 9 Oct 2026
- Optimization controls
- Command-line options control the number of iterations, candidate prompts per iteration, and score threshold for stopping.checked 9 Oct 2026
- Product
- Promptimal is a command-line tool for improving AI prompts without needing a dataset.checked 9 Oct 2026
- Progress UI
- The optimization process can be monitored in a UI opened in the terminal.checked 9 Oct 2026
- Provider roadmap
- The README lists support for other LLM providers, including Anthropic, Groq, and Ollama, as roadmap items.checked 9 Oct 2026
- Roadmap
- The roadmap lists support for other LLM providers, including Anthropic and Groq, and local models through Ollama, as planned work.checked 9 Oct 2026
- Terminal interface
- After starting an optimization, users can monitor its progress in a UI in their terminal.checked 9 Oct 2026
- What it does
- Promptimal is a command-line tool that iteratively improves AI prompts using a genetic algorithm, without requiring a dataset.checked 9 Oct 2026
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