On December 20, 2025, we are excited to launch prompt2json, a Unix-style CLI tool that brings machine-reliability to LLM outputs. By leveraging Gemini models via Vertex AI, prompt2json allows developers to enforce strict output shapes using JSON Schema, making LLMs a dependable part of shell pipelines and automated workflows.

Introducing prompt2json

prompt2json is designed for those who need the intelligence of a Large Language Model but the predictability of a structured data format. Instead of wrestling with “hallucinated” formatting or inconsistent JSON, prompt2json ensures that your model’s response adheres strictly to a predefined schema.

Key capabilities include:

  • Schema-Validated Output: Use JSON Schema to define exactly what your data should look like, ensuring consistency across every call.
  • Unix-First Design: Seamlessly integrates into your favorite shell workflows using STDIN for prompts and STDOUT for clean, validated JSON.
  • Rich Media Support: Beyond text, the tool supports images (PNG, JPG, WebP) and PDFs, allowing you to extract structured data from a variety of visual sources.
  • Developer-Centric Tooling: With flags like --pretty-print for readability and --verbose for tracking token usage and API diagnostics, it’s built for a smooth development and debugging experience.

Why it matters

For many developers, the “last mile” of LLM integration is the most frustrating—parsing the response and handling validation errors. prompt2json eliminates this friction.

By moving validation to the core of the tool and ensuring a clean, uncontaminated output stream, it transforms the LLM from a conversational partner into a reliable data processing utility. Whether you’re building complex data pipelines or simple automation scripts, you can now trust that the output will be exactly what your downstream tools expect, without the need for custom regex or fragile parsing logic.

Getting Started

To get started with prompt2json, you can install it directly using Go:

go install github.com/UnitVectorY-Labs/prompt2json@latest

Alternatively, you can build it from source by cloning the repository and running go build.

Please note that prompt2json requires Google Application Default Credentials (ADC) to interact with Vertex AI. You can set this up by running:

gcloud auth application-default login

prompt2json is more than just a wrapper; it’s a bridge between the flexibility of generative AI and the rigor of structured data. We’re excited to see how you use it to automate and enhance your workflows.

This post was AI-generated. Model: unsloth/gemma-4-31B-it-GGUF:UD-Q5_K_XL Reference: UnitVectorY-Labs/prompt2json, v0.1.0, generated on 2026-04-13 Author: release-storyteller