ai-agent

prompty

Prompty makes it easy to create, manage, debug, and evaluate LLM prompts for your AI applications. Prompty is an asset class and format for LLM prompts

From the repo · “Prompty makes it easy to create, manage, debug, and evaluate LLM prompts for your AI applications. Prompty is an asset class and format for LLM prompts designed to enhance observability, understandability, and portability for developers. ”

1,285 stars+3★ this week132 forksRustUpdated 10/21/2026100% free · open source
What it does

Prompty lets you write, version‑control, debug, and evaluate LLM prompts as portable, observable assets.

When to use it
  • •You need a single source‑of‑truth file for a prompt that multiple services share.
  • •You want to unit‑test or benchmark prompts before shipping to production.
  • •Your team collaborates on prompt engineering and needs versioning and change logs.
Ready-to-paste prompt
```yaml
# greeting.prompty
name: Greeting
model: gpt-4o
template: |
  You are a friendly assistant.
  {{user_message}}
variables:
  - name: user_message
    type: string
    description: Message from the user
```
Heads up: Prompty calls the LLM via the OpenAI API – you must set the `OPENAI_API_KEY` environment variable (or configure another provider) before running any `prompty run/evaluate` commands.
Saves to your device
Use with Claude
New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

✅ Light setup

Installs with a command or two; your AI agent can do it for you.

Try it instantly — no install
Claude Code
mkdir -p ~/.claude/skills/prompty && curl -fsSL https://workflowstacks.com/api/skills/prompty/claude-skill -o ~/.claude/skills/prompty/SKILL.md
Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)
claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

How prompty works
Codeflow
Free to inspect

Prompty is a very large Rust project (~261k lines across 2004 code files, plus 584 test files). Setup is light: installs like a normal app. Reading the code is optional. Last commit this month, MIT license, has a test suite.

Size
Very large codebase
~261k lines · 2004 code files · days to read — use, don't read
Setup
One-command install
Installs like a normal app. Reading the code is optional.
Runs on
Rust
No API keys detected
Rust 18%C# 16%Java 15%Python 15%TypeScript 13%
Where to start reading
  1. 1
    README.md
    Start here — what it does and how to install it
What's in each folder
web/Frontend / UI419 files
runtime/java/Folder457 files
runtime/csharp/Folder444 files
runtime/python/Folder426 files
runtime/typescript/Folder415 files
runtime/rust/Folder342 files
runtime/swift/Folder305 files
runtime/go/Folder281 files
READMEHas testsDocumentedCI checksMIT licenseUpdated this month
Quick Actions
Details
Creator
microsoft
Language
Rust
Category
ai-agent
Published
4/22/2024

Are you the creator of this tool? and earn 85% of every sale.

Show it off in your README:

Featured on WorkflowStacks
[![Featured on WorkflowStacks](https://workflowstacks.com/api/badge/prompty.svg)](https://workflowstacks.com/skills/prompty?utm_source=github&utm_medium=badge)
🔥 Hot this week, in your inbox
Skills like this, every Monday.

The five fastest-growing open-source AI skills, ranked by GitHub star growth. One email a week, unsubscribe anytime.