Modular Prompt Library
Modular Prompt Library is a web platform for building, managing, sharing, testing, and comparing AI prompts.
What Modular Prompt Library is
Modular Prompt Library is a web platform for building, managing, sharing, testing, and comparing AI prompts. Prompts can be assembled from reusable components and reused across projects; version history tracks changes and supports reverting to earlier versions. Teams can share libraries, review changes, and collaborate on prompt development. Testing uses your own OpenAI, Anthropic, or Google API keys. The environment lets you fill variables, tune temperature, top-p, and max tokens per model, and save presets for a prompt version. It compares outputs side by side and shows latency, tokens, and estimated cost; model usage is billed directly by the provider. The Personal Account plan is free for personal use, with up to 5 workspaces and unlimited prompts and modules. Starter is free for up to 5 users or 3 workspaces; Growth costs $2.50 per month and Professional costs $5.00 per month. Organizational accounts have a 60-day free trial, with no credit card required to start. The site says keys are encrypted at rest and prompt content stays in your workspace.
Good
- Reusable prompt components work across projects
- Version history supports reverting to earlier versions
- Compares outputs with latency, token, and cost details
- Free personal plan includes unlimited prompts and modules
Watch out
- Personal Account is for personal use only
- Testing requires your own model-provider API keys
- Model usage is billed directly by the provider
Who it suits
It suits prompt engineers and teams in AI content creation, marketing, software development, customer support, or education. Personal users can organize and test prompts across up to five workspaces.
Verdict
Modular Prompt Library combines prompt organization, collaboration, and model comparisons in one web workspace. Consider whether its workspace limits and the need to supply API keys fit your personal or team workflow.
Plans and prices
From Modular Prompt Library's own pricing page, checked 8 Oct 2001.
| Plan | Price | What it gives you |
|---|---|---|
| Personal Account | Free | Up to 5 workspaces · Unlimited prompts & modules · Prompt testing with own API keys · Personal use only |
| Starter | Free | Up to 5 users OR 3 workspaces · MFA · Team collaboration · Granular user access control · JSON export |
| Growth | $2.50 a month | 6–10 users OR 4–10 workspaces · MFA · Team collaboration · Granular user access control · JSON export · $2.5/month |
| Professional | $5 a month | 11–30 users OR 11–15 workspaces · MFA · Team collaboration · Granular user access control · JSON export · $5/month |
| Enterprise | Priced on request | 30+ users OR 15+ workspaces · MFA · Team collaboration · Granular user access control · JSON export · Custom |
The facts
Each one read from Modular Prompt Library's own pages, with the date it was checked.
What it does
- API key handling
- The site says API keys are encrypted at rest, never shared, and model usage is billed directly by the provider.checked 8 Oct 2001
- Intended users
- The site identifies AI content creation teams, prompt engineers, marketing agencies, software development teams, customer support teams, and educational institutions as audiences.checked 8 Oct 2001
- Model comparisons
- The test environment compares outputs side by side and shows latency, tokens, and estimated cost.checked 8 Oct 2001
- Model integrations
- Users can connect their own OpenAI, Anthropic, and Google API keys to test prompts across models.checked 8 Oct 2001
- Organizational security
- Organizational plans list MFA security, granular user access control, and organizational management.checked 8 Oct 2001
- Product
- Modular Prompt Library is an AI prompt management platform for building, managing, sharing, testing, and comparing prompts.checked 8 Oct 2001
- Prompt controls
- Users can fill prompt variables, tune temperature, top-p, and max tokens per model, and save presets per prompt version.checked 8 Oct 2001
- Reusable modules
- Users can build prompts from reusable components and combine them across projects.checked 8 Oct 2001
- Support
- The site provides a support contact form for questions and help with the product.checked 8 Oct 2001
- Version history
- The product tracks prompt changes with version history and supports reverting to previous versions.checked 8 Oct 2001
- Workspace privacy
- The site says prompts, variables, and outputs stay in the user's workspace and that prompt content is never accessed, used, or shared by the maker.checked 8 Oct 2001
Money
- Free tier limits
- The Personal Account plan is for personal use and allows up to 5 workspaces with unlimited prompts and modules.checked 8 Oct 2001
- Trial
- Organizational accounts have a 60-day free trial for all tiers, and the site says no credit card is required to start.checked 8 Oct 2001
The company
- Team collaboration
- Teams can share libraries, review changes, and collaborate on prompt development.checked 8 Oct 2001
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