Jahro Watcher

Help users monitor game variables in real-time using Jahro's [JahroWatch] attribute system.

Workflow

1. Analyze the user's code — identify fields/properties worth monitoring
2. Generate correct [JahroWatch] attributes
3. Add registration if needed (instance members require RegisterObject)
4. VERIFY — "Enter Play Mode, open the Watcher tab, confirm values update"

Analyzing Code for Watcher Candidates

When the user shares a class, identify members worth monitoring:

Good candidates:

• Game state fields: health, score, level, currency, inventory counts
• Physics values: velocity, position, rotation (especially via properties wrapping Rigidbody)
• Performance metrics: FPS, memory, draw calls
• Enum state fields: game state, player state, AI state
• Key counters: enemy count, player count, item count

Skip these:

• Constants and readonly compile-time values
• Private implementation details that change every frame with no debugging value
• References to other objects (Transform, GameObject) — watch their properties instead
• Collections and dictionaries (arrays are supported, but dictionaries are not)

Suggest replacing Debug.Log polling: If the user has Debug.Log($"Health: {health}") in Update(), recommend [JahroWatch] instead — it eliminates log spam and provides a clean real-time dashboard.

Attribute Syntax

[JahroWatch("Display Name", "GroupName", "Description for detail modal")]

Constructor: [JahroWatch(string name, string group, string description)]

All parameters are optional. Defaults: name = member name (leading _ stripped), group = "Default", description = "".

Complete example

using JahroConsole;
using UnityEngine;

public class PlayerController : MonoBehaviour
{
    [JahroWatch("Health", "Player", "Current hit points")]
    public float health = 100f;

    [JahroWatch("Stamina", "Player", "Current stamina")]
    public float stamina = 50f;

    [JahroWatch("Position", "Player", "World position")]
    public Vector3 Position => transform.position;

    [JahroWatch("Velocity", "Player", "Movement velocity")]
    public Vector3 Velocity => GetComponent<Rigidbody>().velocity;

    [JahroWatch("Is Grounded", "Player", "Touching ground")]
    public bool isGrounded;

    void OnEnable()  => Jahro.RegisterObject(this);
    void OnDisable() => Jahro.UnregisterObject(this);
}

Registration

Instance members — require RegisterObject

void OnEnable()  => Jahro.RegisterObject(this);
void OnDisable() => Jahro.UnregisterObject(this);

This same call also registers [JahroCommand] attributes on the class. If the class already has RegisterObject for commands, do not add a second call — one call handles both.

Read references/common-patterns.md for the canonical lifecycle pattern.

Static members — no registration needed

Static fields and properties with [JahroWatch] are discovered via assembly scanning:

public static class GameStats
{
    [JahroWatch("Total Score", "Game")]
    public static int Score;

    [JahroWatch("Session Time", "Game")]
    public static float SessionTime => Time.realtimeSinceStartup;
}

Adding watchers to a class that already has commands

If the class already has [JahroCommand] attributes and RegisterObject, just add [JahroWatch] attributes — no registration changes:

public class GameManager : MonoBehaviour
{
    // Existing command
    [JahroCommand("reset-game", "Game", "Reset game")]
    public void ResetGame() { /* ... */ }

    // New watchers — just add attributes
    [JahroWatch("Player Count", "Game")]
    public int playerCount;

    [JahroWatch("Game Time", "Game")]
    public float gameTime;

    // Already present — no changes needed
    void OnEnable()  => Jahro.RegisterObject(this);
    void OnDisable() => Jahro.UnregisterObject(this);
}

Supported Types

Type	List View Display	Detail Modal
int, float, double, bool	Value as-is	Same
string	Truncated	Full text
Vector2	Compact coords	Coords + magnitude
Vector3	Compact coords	Coords + magnitude
Quaternion	Raw values	Raw + Euler angles
Transform	Position	Position, rotation, scale, child count
Rigidbody	Summary	Mass, kinematic, gravity, velocity, angular velocity
Collider	Summary	Trigger status, material, bounds
AudioSource	Summary	Clip, volume, loop, pitch, mute
Camera	Summary	FOV, clip planes, aspect ratio
Arrays (any T[])	TypeName[length]	Full contents

For custom types not in this table, the watcher calls .ToString(). If you need rich display, consider watching individual primitive properties instead.

Read references/api-reference.md for the full type display details.

Performance

Watchers are designed to be safe for development and testing:

• Values are only read when the Watcher UI tab is visible. No continuous polling when the console is closed or on another tab.
• No overhead when disabled. If Jahro is disabled via JAHRO_DISABLE or auto-disable, watchers are never evaluated.
• Be mindful of expensive property getters. A property like public int Count => expensiveList.Where(...).Count() runs its getter every frame the Watcher is open. Cache expensive computations.

Performance-safe property pattern

private float _cachedFps;
private float _lastFpsUpdate;

void Update()
{
    if (Time.time - _lastFpsUpdate > 0.25f)
    {
        _cachedFps = 1f / Time.unscaledDeltaTime;
        _lastFpsUpdate = Time.time;
    }
}

[JahroWatch("FPS", "Performance")]
public float FPS => _cachedFps;

Group Organization

By system (recommended default)

"Player"      — Health, Stamina, Position, Velocity
"Physics"     — Is Grounded, Angular Velocity, Collision Count
"Performance" — FPS, Memory, Draw Calls
"Game"        — Game State, Level Progress, Player Count
"AI"          — AI State, Target, Path Length

By priority

"Critical"    — Health, Frame Time (always need these)
"Gameplay"    — Enemy Count, Spawn Timer
"Diagnostics" — GC Allocs, Memory

Watcher UI behavior

• Favorites group always appears at top (user stars individual watchers)
• Custom groups are alphabetically sorted
• Groups are collapsible to reduce clutter
• Tapping a watcher opens a detail modal with description and full type info

Contextual Awareness

Pattern in code	Suggestion
Debug.Log in Update() logging variable values	Replace with [JahroWatch] — cleaner, no log spam
[JahroWatch] already present	Suggest additional watchers, better groups, performance tips
[JahroCommand] but no watchers	Suggest adding watchers for key state the commands modify
Rigidbody or physics-heavy code	Suggest velocity, angular velocity, isGrounded watchers
Game manager with state fields	Suggest watching game state enum, counts, timers

Verification

After generating watchers, always include:

Verify: Enter Play Mode → press ~ → switch to the Watcher tab. Confirm your watched values appear in the correct groups and update in real-time as the game runs. Tap a watcher to see its detail modal.

If watchers appear but don't update, or don't appear at all, suggest the jahro-troubleshooting skill — common causes: missing RegisterObject, Watcher tab not open, object destroyed without unregistering.