Promptimal vs Vellum
Promptimal
github.comVellum
vellum.aiSide by side
| Figure | Promptimal | Vellum |
|---|---|---|
| Price from | — | $30/mo |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | Yes |
| Web | — | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | Yes | — |
| iOS | — | Yes |
| Android | — | Yes |
| API | — | Yes |
| Self-hosted | — | Yes |
| Plans published | 0 | 9 |
| Spec score · AI Prompt Generators | 6.9 (#23) | 8.6 (#5) |
| Product | Promptimal is a command-line tool for improving AI prompts without needing a dataset. | Vellum describes itself as a personal AI assistant that can read files, manage calendars, send email, run code, and control a computer. |
| What it does | Promptimal is a command-line tool that iteratively improves AI prompts using a genetic algorithm, without requiring a dataset. | Vellum is a personal AI assistant that can read files, manage calendars, control computers, take calls, perform transactions, and retain personal context. |
Plans
Vellum
- BaseFree
- FreeFree
- Mighty$30 a month
- Mighty$30 a month
- Custom$50 a month
- Super$100 a month
- Super$100 a month
- Ultra$200 a month
- Ultra$200 a month
In their own words
Vellum
Vellum is a personal AI assistant that can read files, manage calendars, send email, run code, and control a computer. It saves preferences and context in its workspace for later conversations, and users can create, install, and manage skills. Listed OAuth services include Discord, GitHub, Google services, HubSpot, Linear, Twitter (X), Asana, Notion, Microsoft Outlook, and Todoist. Vellum says OAuth tokens stay in a credential vault rather than being exposed to the language model. Sensitive actions prompt for approval, and users can set trust rules for standing permissions. By default, conversation context is sent to Anthropic to generate responses; OpenAI, Google, OpenRouter, Fireworks, and local Ollama are listed alternatives. An internet connection is required. Vellum Cloud runs assistants in isolated environments with private storage and 24/7 availability. The Free plan includes first tasks and pay-as-you-go credits. Mighty costs $30 a month, Super $100 a month, and Ultra $200 a month. There is no shipped Linux desktop client, but Linux users can use the web app, Chrome extension, or self-host the runtime.