get_track_info_by_index

Instructions

Implementation Reference

• src/main.ts:120-149 (registration)

  Tool registered with name 'get_track_info_by_index'. Uses server.tool() with a description, input schema (filePath: string, trackIndex: number), and handler wrapped in withErrorHandling.

  server.tool(
      'get_track_info_by_index',
      `Get track info from midi file by track index. 
      name, instrument, channel, endOfTrackTicks, duration, durationTicks, noteCount`,
      {
          filePath: z.string().describe('Absoulate File Path to midi file'),
          trackIndex: z.number().describe('Track index number'),
      },
      withErrorHandling(({ filePath, trackIndex }) => {
          const midi = loadMidiFile(filePath)
          const track = getTrackByIndex(midi, trackIndex)
          const trackInfo = {
              name: track.name,
              instrument: track.instrument.toJSON(),
              channel: track.channel,
              endOfTrackTicks: track.endOfTrackTicks,
              duration: track.duration,
              durationTicks: track.durationTicks,
              noteCount: track.notes.length,
          }
          return {
              content: [
                  {
                      type: 'text',
                      text: JSON.stringify(trackInfo),
                  },
              ]
          }
      })
  )

• src/main.ts:128-148 (handler)

  Handler function that loads the MIDI file, gets the track by index, extracts name, instrument, channel, endOfTrackTicks, duration, durationTicks, and noteCount, then returns the info as JSON.

  withErrorHandling(({ filePath, trackIndex }) => {
      const midi = loadMidiFile(filePath)
      const track = getTrackByIndex(midi, trackIndex)
      const trackInfo = {
          name: track.name,
          instrument: track.instrument.toJSON(),
          channel: track.channel,
          endOfTrackTicks: track.endOfTrackTicks,
          duration: track.duration,
          durationTicks: track.durationTicks,
          noteCount: track.notes.length,
      }
      return {
          content: [
              {
                  type: 'text',
                  text: JSON.stringify(trackInfo),
              },
          ]
      }
  })

• src/main.ts:124-127 (schema)

  Input schema using Zod: filePath is a string, trackIndex is a number.

  {
      filePath: z.string().describe('Absoulate File Path to midi file'),
      trackIndex: z.number().describe('Track index number'),
  },

• src/main.ts:23-39 (helper)

  Error handling wrapper used by the tool. Catches any errors and returns an error response.

  const withErrorHandling = <T extends Record<string, any>>(handler: (args: T) => any) => {
      return async (args: T) => {
          try {
              return await handler(args)
          } catch (e) {
              return {
                  isError: true,
                  content: [
                      {
                          type: 'text',
                          text: `Error: ${e}`,
                      },
                  ]
              }
          }
      }
  }

• src/utils/file-util.ts:5-9 (helper)

  Loads a MIDI file from disk using @tonejs/midi library.

  export function loadMidiFile(filePath: string) {
      const midiData = fs.readFileSync(filePath)
      const midi = new Midi(midiData)
      return midi
  }