moeru-ai/airi · warning · Error

Please specify a player name!

Error message

Please specify a player name!

What it means

Thrown by the 'follow' command handler in FollowCommand when ctx.command.sender is falsy. The command expects a player name as the sender/argument; without it the plugin cannot resolve a target. This is an input-validation guard at the command boundary.

Source

Thrown at integrations/minecraft/src/plugins/follow.ts:49

        if (!state.following)
          return

        const target = bot.bot.players[state.following]?.entity
        if (!target) {
          state.following = undefined
          throw new Error('Player not found, stopped following')
        }

        const { x: playerX, y: playerY, z: playerZ } = target.position

        bot.bot.pathfinder.setMovements(state.movements)
        bot.bot.pathfinder.setGoal(new goals.GoalNear(playerX, playerY, playerZ, options?.rangeGoal ?? 1))
      }

      bot.onCommand('follow', (ctx) => {
        const username = ctx.command!.sender
        if (!username) {
          throw new Error('Please specify a player name!')
        }

        startFollow(username)
      })

      bot.onCommand('stop', () => {
        stopFollow()
      })

      bot.onTick('tick', () => {
        if (state.following)
          followPlayer()
      })
    },
  }
}

View on GitHub (pinned to 27111382b4)

Solutions

1. Provide the target player name: 'follow Steve'.
2. If invoking programmatically, ensure the command context carries a sender.
3. Add a usage hint in the thrown message so the user knows the expected syntax.

Example fix

// before
//   bot.onCommand('follow', (ctx) => {
//     const username = ctx.command!.sender
//     if (!username) { throw new Error('Please specify a player name!') }
//     startFollow(username)
//   })
//
// after (clearer usage + graceful message)
//   bot.onCommand('follow', (ctx) => {
//     const username = ctx.command!.sender
//     if (!username) { logger.log('Usage: follow <player>'); return }
//     startFollow(username)
//   })

// Validate sender before starting follow:
// const username = ctx.command?.sender
// if (!username) { logger.log('Usage: follow <player>'); return }

function hasSender(ctx: unknown): ctx is { command: { sender: string } } {
  return !!ctx && typeof ctx === 'object'
    && !!(ctx as any).command && typeof (ctx as any).command.sender === 'string'
}

When it happens

Trigger: A player sends the bare command 'follow' with no argument and the command context's sender is empty; the command parser did not populate sender; the command was invoked programmatically (e.g. from a tick or another plugin) with no sender context.

Common situations: User types 'follow' instead of 'follow Steve'; command framework change that stopped populating sender; invoking the handler directly from non-command code.

Related errors

• no player name specified
• Player not found, stopped following
• Unknown action: ${step.tool}
• RESOURCE_MISSING
• TARGET_NOT_FOUND

AI-assisted analysis of moeru-ai/airi@27111382b4 (2026-08-12). Data as JSON: /api/errors/79a665bfdc2746a9. Report an issue: GitHub.