go

README

Go Dotprompt

Executable GenAI prompt templates in Go.

Overview

This library provides a Go implementation of the Dotprompt format -- a language-neutral executable prompt template format for Generative AI. It passes all shared spec tests for cross-language compatibility.

Features

• YAML frontmatter for prompt metadata (model, config, input/output schemas)
• Handlebars templating with 7 built-in helpers (role, media, history, section, json, ifEquals, unlessEquals)
• Picoschema: compact schema notation with JSON Schema conversion
• Multi-message prompts with role markers
• Named partials with recursive resolution and cycle detection
• PromptStore interface with DirStore (file system) implementation
• Custom loaders and schema/tool resolvers
• Tools/functions and safety settings via config passthrough
• 200+ spec tests passing

Installation

go get github.com/google/dotprompt/go/dotprompt

Usage

package main

import (
    "fmt"
    "github.com/google/dotprompt/go/dotprompt"
)

func main() {
    dp := dotprompt.New(nil)
    source := `---
model: gemini-2.0-flash
input:
  schema:
    name: string
---
Hello, {{name}}!`

    data := dotprompt.DataArgument{
        Input: map[string]any{"name": "World"},
    }
    rendered, err := dp.Render(source, data, nil)
    if err != nil {
        panic(err)
    }
    fmt.Println(rendered.Prompt.Messages[0].Content[0].Text)
}

Building

go build ./...

Testing

go test -v ./...

Published Package

• pkg.go.dev: github.com/google/dotprompt/go/dotprompt

License

Apache-2.0