Ratings and Reviews 0 Ratings

Total 0 out of 5 stars
ease 0 out of 5 stars
features 0 out of 5 stars
design 0 out of 5 stars
support 0 out of 5 stars

This software has no reviews. Be the first to write a review.

Write a Review

Ratings and Reviews 0 Ratings

Total 0 out of 5 stars
ease 0 out of 5 stars
features 0 out of 5 stars
design 0 out of 5 stars
support 0 out of 5 stars

This software has no reviews. Be the first to write a review.

Write a Review

Alternatives to Consider

  • Google AI Studio Reviews & Ratings
    4.8 out of 5 stars 42 Ratings
    Company Website for Google AI Studio
  • Checksum.ai Reviews & Ratings
    5.0 out of 5 stars 2 Ratings
    Company Website for Checksum.ai
  • Apify Reviews & Ratings
    4.8 out of 5 stars 1,800 Ratings
    Company Website for Apify
  • AI Video Cut Reviews & Ratings
    5.0 out of 5 stars 1 Rating
    Company Website for AI Video Cut
  • SmartDraw Reviews & Ratings
    4.4 out of 5 stars 573 Ratings
    Company Website for SmartDraw
  • Adobe Firefly Reviews & Ratings
    4.3 out of 5 stars 25,051 Ratings
    Company Website for Adobe Firefly
  • HubSpot AEO Reviews & Ratings
    4.4 out of 5 stars 151 Ratings
    Company Website for HubSpot AEO
  • NodeMaven Reviews & Ratings
    4.8 out of 5 stars 1,088 Ratings
    Company Website for NodeMaven
  • Evertune Reviews & Ratings
    5.0 out of 5 stars 1 Rating
    Company Website for Evertune
  • Aikido Security Reviews & Ratings
    4.6 out of 5 stars 364 Ratings
    Company Website for Aikido Security

What is LangFast?

LangFast is a lightweight yet powerful prompt testing platform tailored for product teams, prompt engineers, and developers working extensively with large language models (LLMs). Offering instant, no-signup access to a fully customizable prompt playground, it simplifies the creation and testing of prompt templates using Jinja2 syntax. Users can see real-time raw outputs directly from the LLM without any API abstractions, enabling precise control and immediate feedback. By eliminating manual testing friction, LangFast allows teams to validate prompts, iterate rapidly, and collaborate more effectively on prompt development projects. Created by a team with a proven track record of scaling AI SaaS platforms to over 15 million users, the platform emphasizes control and scalability. LangFast supports seamless sharing of prompt templates, making teamwork intuitive and efficient. Its simple pay-as-you-go pricing model ensures cost predictability and accessibility for teams of all sizes. The platform’s clean and lightweight design means it can be integrated easily into existing workflows without overhead. LangFast empowers teams to accelerate innovation in prompt engineering while managing expenses effectively. This makes it an ideal choice for organizations looking to enhance their AI-driven product development with flexible and transparent prompt testing.

What is Agenta?

Agenta is a full-featured, open-source LLMOps platform designed to solve the core challenges AI teams face when building and maintaining large language model applications. Most teams rely on scattered prompts, ad-hoc experiments, and limited visibility into model behavior; Agenta eliminates this chaos by becoming a central hub for all prompt iterations, evaluations, traces, and collaboration. Its unified playground allows developers and product teams to compare prompts and models side-by-side, track version changes, and reuse real production failures as test cases. Through automated evaluation workflows—including LLM-as-a-judge, built-in evaluators, human feedback, and custom scoring—Agenta provides a scientific approach to validating prompts and model updates. The platform supports step-level evaluation, making it easier to diagnose where an agent’s reasoning breaks down instead of inspecting only the final output. Advanced observability tools trace every request, display error points, collect user feedback, and allow teams to annotate logs collaboratively. With one click, any trace can be turned into a long-term test, creating a continuous feedback loop that strengthens reliability over time. Agenta’s UI empowers domain experts to experiment with prompts without writing code, while APIs ensure developers can automate workflows and integrate deeply with their stack. Compatibility with LangChain, LlamaIndex, OpenAI, and any model provider ensures full flexibility without vendor lock-in. Altogether, Agenta accelerates the path from prototype to production, enabling teams to ship robust, well-tested LLM features and intelligent agents faster.

Media

No images available

Media

Integrations Supported

Integrations Supported

Cohere
Falcon AI
Hugging Face
LangChain
Llama
Llama 2
Llama 3
Llama 3.1
Llama 3.2
Llama 3.3
OpenAI
Python

API Availability

API Availability

Has API

Pricing Information

$60 one time
Free Trial Offered?

Pricing Information

Free
Free Version

Supported Platforms

SaaS

Supported Platforms

SaaS

Customer Service / Support

Not specified

Customer Service / Support

24 Hour Support
Web-Based Support

Training Options

Not specified

Training Options

Documentation Hub
Online Training

Company Facts

Organization Name

Langfa.st

Date Founded

2025

Company Location

United States

Company Website

langfa.st/new

Company Facts

Organization Name

Agenta

Date Founded

2023

Company Location

Germany

Company Website

agenta.ai/

Categories and Features

Prompt Engineering

Not specified

Categories and Features

Prompt Engineering

Not specified

Prompt Management

Not specified

Popular Alternatives

Popular Alternatives