fix: rename start_beat to start and end_beat to end in 3 tools.

public/prompts/system.md

@@ -25,9 +25,9 @@ Read existing musical content from the project. The output is in ABC notation. I
 Remove notes from a given beat range in the current region.
 
 ## add_notes
-Add notes to the current region. Pitches use scientific pitch notation with support for sharps and flats (e.g., `C4`, `F#3`, `Bb2`). **Important**: the `start_beat` parameter is always the **absolute** beat position in the project timeline — not relative to the current region's start. For example, to place a note at beat 6, set `start_beat` to 6 regardless of where the current region begins.
+Add notes to the current region. Pitches use scientific pitch notation with support for sharps and flats (e.g., `C4`, `F#3`, `Bb2`). **Important**: the `start` parameter is always the **absolute** beat position in the project timeline — not relative to the current region's start. For example, to place a note at beat 6, set `start` to 6 regardless of where the current region begins.
 
-To create a melodic line, use sequential `start_beat` values for each note. To create a chord, give multiple notes the same `start_beat`.
+To create a melodic line, use sequential `start` values for each note. To create a chord, give multiple notes the same `start`.
 
 # Tool Use Guidelines
 
@@ -80,12 +80,12 @@ You have access to two tools for working with the current music region: **remove
   - Check that chord progressions are appropriate for the key signature
   - Confirm note lengths don't extend beyond reasonable musical phrases
 - **Pitch Notation**: Use scientific pitch notation (e.g., C4, A#3, Bb2) and ensure octave numbers are appropriate for the instrument
-- **Timing Constraints**: All start_beat and length values must align with the time signature grid
+- **Timing Constraints**: All start and length values must align with the time signature grid
 - When adding chord progressions, first break down the progression into individual notes based on the key signature, then add all the notes.
 - For example, to create a I-V-vi-IV progression in C major with 4-beat chords:
   1. Check the key signature. In C major, the chords are C, G, Am, F.
   2. Convert each chord to individual notes: C = C4/E4/G4, G = G3/B3/D4, Am = A3/C4/E4, F = F3/A3/C4.
-  3. Call `add_notes` with all 12 notes: the C chord notes at `start_beat` 0, the G chord notes at `start_beat` 4, the Am chord notes at `start_beat` 8, and the F chord notes at `start_beat` 12 — each with `length` 4.
+  3. Call `add_notes` with all 12 notes: the C chord notes at `start` 0, the G chord notes at `start` 4, the Am chord notes at `start` 8, and the F chord notes at `start` 12 — each with `length` 4.
 
 # Workflow Tips
 

src/agent/tools/AddNotesTool.ts

@@ -17,7 +17,7 @@ export class AddNotesTool extends BaseTool {
   readonly parameters: Record<string, ToolParameter> = {
     notes: {
       type: 'array',
-      description: 'List of notes to add. To create a chord, give multiple notes the same start_beat. To create a melody, use sequential start_beat values.',
+      description: 'List of notes to add. To create a chord, give multiple notes the same start beat. To create a melody, use sequential start values.',
       required: true,
       items: {
         type: 'object',
@@ -28,9 +28,9 @@ export class AddNotesTool extends BaseTool {
             description: 'Pitch in scientific notation: note name, optional accidental (# or b), and octave number. Examples: "C4" (middle C), "F#3" (F-sharp 3rd octave), "Bb2" (B-flat 2nd octave).',
             required: true
           },
-          start_beat: {
+          start: {
             type: 'number',
-            description: 'Absolute beat position on the project timeline where the note starts. This is NOT relative to the region — beat 6 means beat 6 in the project regardless of where the region begins. Fractional values are supported (e.g., 0.5 = half a beat after beat 0).',
+            description: 'Start beat — the absolute beat position on the project timeline where the note begins. This is NOT relative to the region — beat 6 means beat 6 in the project regardless of where the region begins. Fractional values are supported (e.g., 0.5 = half a beat after beat 0).',
             required: true
           },
           length: {
@@ -60,7 +60,7 @@ export class AddNotesTool extends BaseTool {
       
       const notes = params.notes as Array<{
         pitch: string;
-        start_beat: number;
+        start: number;
         length: number;
         velocity?: number;
       }>;
@@ -79,7 +79,7 @@ export class AddNotesTool extends BaseTool {
 
       // Validate and convert notes to creation data
       const noteCreationData: NoteCreationData[] = [];
-      const createdNotes: Array<{ pitch: string; start_beat: number; length: number }> = [];
+      const createdNotes: Array<{ pitch: string; start: number; length: number }> = [];
       
       for (const note of notes) {
         try {
@@ -92,8 +92,8 @@ export class AddNotesTool extends BaseTool {
           }
           
           // Validate beat positions
-          if (note.start_beat < 0) {
+          if (note.start < 0) {
-            return this.createErrorResult(`Invalid start_beat ${note.start_beat}. Must be >= 0.`);
+            return this.createErrorResult(`Invalid start ${note.start}. Must be >= 0.`);
           }
           
           if (note.length <= 0) {
@@ -102,7 +102,7 @@ export class AddNotesTool extends BaseTool {
           
           // Adjust note position relative to region's start beat
           const regionStartBeat = targetRegion.getStartFromBeat();
-          const adjustedStartBeat = note.start_beat - regionStartBeat;
+          const adjustedStartBeat = note.start - regionStartBeat;
           const adjustedEndBeat = adjustedStartBeat + note.length;
           
           // Create note creation data
@@ -116,7 +116,7 @@ export class AddNotesTool extends BaseTool {
           
           createdNotes.push({
             pitch: note.pitch,
-            start_beat: note.start_beat,
+            start: note.start,
             length: note.length
           });
           
@@ -132,7 +132,7 @@ export class AddNotesTool extends BaseTool {
       // Create success message
       const noteCount = createdNotes.length;
       const noteList = createdNotes
-        .map(note => `${note.pitch} (beat ${note.start_beat}, length ${note.length})`)
+        .map(note => `${note.pitch} (beat ${note.start}, length ${note.length})`)
         .join(', ');
       
       return this.createSuccessResult(

src/agent/tools/ReadMusicTool.ts

@@ -20,9 +20,9 @@ export class ReadMusicTool extends BaseTool {
       description: 'Which track to read. Pass a specific track ID, or "all" to read every track. If omitted, reads the first available track.',
       required: false
     },
-    start_beat: {
+    start: {
       type: 'number',
-      description: 'Absolute beat position to start reading from. The actual output will be rounded down to the nearest bar boundary. Defaults to 0.',
+      description: 'Start beat — the absolute beat position to start reading from. The actual output will be rounded down to the nearest bar boundary. Defaults to 0.',
       required: false
     },
     length: {
@@ -57,7 +57,7 @@ export class ReadMusicTool extends BaseTool {
       this.validateParameters(params);
 
       const trackId = params.track_id as string | undefined;
-      const startBeat = (params.start_beat as number) || 0;
+      const startBeat = (params.start as number) || 0;
       const length = params.length as number | undefined;
 
       const project = this.getCurrentProject();
@@ -67,9 +67,9 @@ export class ReadMusicTool extends BaseTool {
         return this.createErrorResult('No tracks found in the project');
       }
 
-      // Validate start_beat
+      // Validate start
       if (startBeat < 0) {
-        return this.createErrorResult(`Invalid start_beat ${startBeat}. Must be >= 0.`);
+        return this.createErrorResult(`Invalid start ${startBeat}. Must be >= 0.`);
       }
 
       // Validate length

src/agent/tools/RemoveNotesTool.ts

@@ -14,14 +14,14 @@ export class RemoveNotesTool extends BaseTool {
   readonly description = 'Remove all MIDI notes whose start position falls within the specified beat range. Use this to clear a section before rewriting it, or to delete unwanted notes. Beat positions are absolute on the project timeline.';
 
   readonly parameters: Record<string, ToolParameter> = {
-    start_beat: {
+    start: {
       type: 'number',
-      description: 'Absolute beat position where the removal range begins (inclusive). A note starting at exactly this beat will be removed.',
+      description: 'Start beat — the absolute beat position where the removal range begins (inclusive). A note starting at exactly this beat will be removed.',
       required: true
     },
-    end_beat: {
+    end: {
       type: 'number',
-      description: 'Absolute beat position where the removal range ends (exclusive). A note starting at exactly this beat will NOT be removed. Must be greater than start_beat.',
+      description: 'End beat — the absolute beat position where the removal range ends (exclusive). A note starting at exactly this beat will NOT be removed. Must be greater than start.',
       required: true
     },
     region_id: {
@@ -36,17 +36,17 @@ export class RemoveNotesTool extends BaseTool {
       // Validate parameters
       this.validateParameters(params);
       
-      const startBeat = params.start_beat as number;
+      const startBeat = params.start as number;
-      const endBeat = params.end_beat as number;
+      const endBeat = params.end as number;
       const regionId = params.region_id as string | undefined;
       
       // Validate beat range
       if (startBeat < 0) {
-        return this.createErrorResult(`Invalid start_beat ${startBeat}. Must be >= 0.`);
+        return this.createErrorResult(`Invalid start ${startBeat}. Must be >= 0.`);
       }
 
       if (endBeat <= startBeat) {
-        return this.createErrorResult(`Invalid beat range: end_beat (${endBeat}) must be greater than start_beat (${startBeat}).`);
+        return this.createErrorResult(`Invalid beat range: end (${endBeat}) must be greater than start (${startBeat}).`);
       }
       
       // Find the target region

src/core/KGDebugger.ts

@@ -268,13 +268,13 @@ export class KGDebugger {
    * Usage examples in browser console:
    *
    *   // Single tool call:
-   *   await KGStudio.KGDebugger.testToolCall('{"name":"read_music","arguments":{"start_beat":0,"length":8}}')
+   *   await KGStudio.KGDebugger.testToolCall('{"name":"read_music","arguments":{"start":0,"length":8}}')
    *
    *   // Multiple tool calls:
-   *   await KGStudio.KGDebugger.testToolCall('[{"name":"remove_notes","arguments":{"start_beat":0,"end_beat":4}},{"name":"add_notes","arguments":{"notes":[{"pitch":"C4","start_beat":0,"length":1}]}}]')
+   *   await KGStudio.KGDebugger.testToolCall('[{"name":"remove_notes","arguments":{"start":0,"end_beat":4}},{"name":"add_notes","arguments":{"notes":[{"pitch":"C4","start":0,"length":1}]}}]')
    *
    *   // Can also pass a JS object directly (no need to stringify):
-   *   await KGStudio.KGDebugger.testToolCall({name:"read_music",arguments:{start_beat:0}})
+   *   await KGStudio.KGDebugger.testToolCall({name:"read_music",arguments:{start:0}})
    *
    * @param input - JSON string, object, or array of tool call(s).
    *   Each tool call should have: { name: string, arguments: object }
@@ -352,9 +352,9 @@ export class KGDebugger {
     console.log("  - Use browser developer tools for best experience");
     console.log("");
     console.log("💡 testToolCall examples:");
-    console.log('  await KGStudio.KGDebugger.testToolCall(\'{"name":"read_music","arguments":{"start_beat":0,"length":8}}\')');
+    console.log('  await KGStudio.KGDebugger.testToolCall(\'{"name":"read_music","arguments":{"start":0,"length":8}}\')');
-    console.log('  await KGStudio.KGDebugger.testToolCall({name:"add_notes",arguments:{notes:[{pitch:"C4",start_beat:0,length:1}]}})');
+    console.log('  await KGStudio.KGDebugger.testToolCall({name:"add_notes",arguments:{notes:[{pitch:"C4",start:0,length:1}]}})');
-    console.log('  await KGStudio.KGDebugger.testToolCall([{name:"remove_notes",arguments:{start_beat:0,end_beat:4}},{name:"read_music",arguments:{}}])');
+    console.log('  await KGStudio.KGDebugger.testToolCall([{name:"remove_notes",arguments:{start:0,end_beat:4}},{name:"read_music",arguments:{}}])');
   }
 
   /**