feat(docs): Add comprehensive CLI documentation suite

fusion/src/about_cli.md

@@ -4,12 +4,16 @@
 <!-- MarkdownJ can't handle backticks in headers -->
 # About the <code>fusion</code> CLI
 
-The `fusion` command-line interface is intended to support evaluation of Fusion code across a 
-variety of use cases.  It provides a number of commands that can be composed in a sequence of 
-steps within a single execution of the CLI.
+The `fusion` command-line interface is a powerful tool for evaluating Fusion code across a variety of use cases. It provides multiple commands that can be composed in sequences to build complex data processing workflows.
 
-> ⚠️ This document is a work in progress! We'd love to hear your feedback in 
-> [this Discussion thread](https://github.com/orgs/ion-fusion/discussions/213).
+> **📚 Looking for comprehensive CLI documentation?**
+> 
+> * **[CLI Quick Start](cli_quickstart.html)** - Get started in minutes
+> * **[CLI Tutorial](tutorial_cli.html)** - Step-by-step learning guide  
+> * **[CLI Reference](cli_reference.html)** - Complete command documentation
+> * **[CLI Troubleshooting](cli_troubleshooting.html)** - Common issues and solutions
+
+This document provides an overview of CLI concepts and design principles.
 
 The `fusion` executable requires at least one argument: a command to perform.
 

fusion/src/cli_quickstart.md

@@ -0,0 +1,222 @@
+<!-- Copyright Ion Fusion contributors. All rights reserved. -->
+<!-- SPDX-License-Identifier: Apache-2.0 -->
+
+# Ion Fusion CLI Quick Start
+
+Get up and running with the Ion Fusion CLI in minutes. This guide covers installation, basic usage, and your first Fusion programs.
+
+## Installation
+
+### Option 1: Build from Source (Recommended)
+
+**Prerequisites:**
+- Java 8 or later ([Corretto](https://aws.amazon.com/corretto/) recommended)
+- Git
+
+**Steps:**
+```bash
+# Clone the repository
+git clone https://github.com/ion-fusion/fusion-java.git
+cd fusion-java
+
+# Build the CLI
+./gradlew release
+
+# Add to PATH
+export PATH=$PATH:$PWD/build/install/fusion/bin
+
+# Verify installation
+fusion version
+```
+
+### Option 2: Download Pre-built Binary *(Coming Soon)*
+
+Pre-built binaries will be available from the [releases page](https://github.com/ion-fusion/fusion-java/releases) once version 1.0 is released.
+
+## First Steps
+
+### 1. Verify Installation
+
+```bash
+fusion help
+```
+
+You should see a list of available commands.
+
+### 2. Your First Expression
+
+```bash
+fusion eval '(+ 1 2 3)'
+```
+**Output:** `6`
+
+### 3. Working with Data
+
+```bash
+# Create a simple data structure
+fusion eval '{ name: "Alice", age: 30, hobbies: ["reading", "coding"] }'
+```
+
+**Output:** `{name:"Alice",age:30,hobbies:["reading","coding"]}`
+
+### 4. Interactive Mode
+
+```bash
+fusion repl
+```
+
+Try these expressions in the REPL:
+```fusion
+$ (define greeting "Hello, Fusion!")
+$ greeting
+"Hello, Fusion!"
+$ (define (square x) (* x x))
+$ (square 5)
+25
+$ (exit)
+```
+
+## Essential Commands
+
+### `eval` - Quick Expressions
+Perfect for one-liners and testing:
+```bash
+fusion eval '(* 7 6)'                    # Math: 42
+fusion eval '(string_length "hello")'    # Needs string module
+```
+
+### `load` - Run Scripts
+Create a file `hello.fusion`:
+```fusion
+(define (greet name)
+  (string_append "Hello, " name "!"))
+
+(greet "World")
+```
+
+Run it:
+```bash
+fusion load hello.fusion
+```
+
+### `require` - Import Modules
+```bash
+# Import string functions, then use them
+fusion require '/fusion/string' ';' eval '(string_length "test")'
+```
+
+### `repl` - Interactive Development
+```bash
+fusion repl
+```
+
+## Common Patterns
+
+### Data Processing
+```bash
+# Process Ion data
+echo '{"count": 5}' | fusion eval '(define data (read)) (+ (. data "count") 10)'
+```
+
+### Module Usage
+```bash
+# Use list processing functions
+fusion require '/fusion/list' ';' eval '(map (lambda (x) (* x 2)) [1 2 3 4])'
+```
+
+### Script Development
+Create `process.fusion`:
+```fusion
+// Read input, process it, write output
+(define input (read))
+(define result (* input 2))
+(writeln "Double of " input " is " result)
+result
+```
+
+Use it:
+```bash
+echo "21" | fusion load process.fusion
+```
+
+## Key Concepts
+
+### Ion Data Format
+Fusion uses [Amazon Ion](https://ion-fusion.dev/) as its data format:
+```fusion
+null                    ; Null value
+true false             ; Booleans  
+42 3.14                ; Numbers
+"hello"                ; Strings
+[1, 2, 3]              ; Lists
+{name: "Alice"}        ; Structures (like JSON objects)
+(+ 1 2)                ; S-expressions (function calls)
+```
+
+### Everything is Data
+In Fusion, code is data and data is code:
+```bash
+fusion eval '[1, (+ 2 3), "hello"]'    # Mix data and computation
+```
+
+### Functional Programming
+Functions are first-class values:
+```bash
+fusion eval '(define add (lambda (x y) (+ x y))) (add 10 20)'
+```
+
+## Next Steps
+
+### Learn More Commands
+```bash
+fusion help eval       # Detailed help for eval command
+fusion help load       # Detailed help for load command
+```
+
+### Explore Standard Library
+```bash
+# See what's available
+fusion require '/fusion' ';' repl
+
+# In REPL, try:
+$ (help)               # General help
+$ (help +)             # Help for specific function
+```
+
+### Read the Documentation
+- [Complete CLI Reference](cli_reference.html) - All commands and options
+- [CLI Tutorial](tutorial_cli.html) - Step-by-step learning
+- [Language Reference](fusion.html) - Complete language documentation
+
+### Try Real Examples
+```bash
+# Data transformation
+fusion eval '(map (lambda (x) {value: x, squared: (* x x)}) [1 2 3 4 5])'
+
+# String processing  
+fusion require '/fusion/string' ';' eval '(string_split "a,b,c,d" ",")'
+
+# File processing (create test.ion with some data first)
+echo '[1, 2, 3, 4, 5]' > test.ion
+fusion eval '(define data (with_ion_from_file "test.ion" read)) (fold + 0 data)'
+```
+
+## Getting Help
+
+### Built-in Help
+```bash
+fusion help                    # List all commands
+fusion help <command>          # Detailed command help
+```
+
+### Community
+Visit the [Ion Fusion Community](https://ion-fusion.dev/community/) page for support resources, discussions, and ways to get involved.
+
+### Documentation
+- [CLI Reference](cli_reference.html) - Complete command reference
+- [Language Tutorial](tutorial_cli.html) - Learn the language
+- [Java API](javadoc/index.html) - For embedding in applications
+
+---
+
+**Ready to dive deeper?** Check out the [complete CLI tutorial](tutorial_cli.html) or explore the [language reference](fusion.html).