I was playing and had some bugs like not rendering some blocks, so I saved the game and quite to menu.
After that I just reloaded the saved game and got this error message.
Build 2650
usrID: aba7b4f8-7381-11e5-ab3f-d4bed9fdc342
P.S. I trying to provide as much information as I can. If you need more information, please ask 
I hope this can be of any help to the developers. 
The entire stack trace:
Page 1:
develop-2650 (x64)stonehearth/services/server/ai/ai_service.luac:116: error in args passed to start_thinking: missing argument “ghost” of type “userdata: 00000070ABC49A78” in “[u:417995 place an item]”.stack traceback:
[C]: ?
[C]: in function ‘error’
stonehearth/services/server/ai/ai_service.luac:116: in function ‘report_error’
stonehearth/services/server/ai/ai_service.luac:148: in function <stonehearth/services/server/ai/ai_service.luac:103>
[C]: in function ‘start_thinking’
…onehearth/services/server/tasks/run_task_action.luac:26: in function ‘_start_stop_thinking’
…onehearth/services/server/tasks/run_task_action.luac:50: in function <…onehearth/services/server/tasks/run_task_action.luac:48>
[C]: in function ‘fn’
stonehearth/services/server/threads/thread.luac:109: in function ‘private_msg’
stonehearth/services/server/threads/thread.luac:168: in function ‘_dispatch_messages’
stonehearth/services/server/threads/thread.luac:128: in function <stonehearth/services/server/threads/thread.luac:123>
…
[C]: in function ‘run’
stonehearth/services/server/ai/compound_action.luac:133: in function <stonehearth/services/server/ai/compound_action.luac:129>
[C]: ?
[C]: ?
[C]: in function ‘run’
stonehearth/components/ai/ai_component.luac:190: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
Page 2:
develop-2650 (x64)stonehearthstack traceback:
[C]: in function ‘start_thinking’
…onehearth/services/server/tasks/run_task_action.luac:26: in function ‘_start_stop_thinking’
…onehearth/services/server/tasks/run_task_action.luac:50: in function <…onehearth/services/server/tasks/run_task_action.luac:48>
[C]: in function ‘fn’
stonehearth/services/server/threads/thread.luac:109: in function ‘private_msg’
stonehearth/services/server/threads/thread.luac:168: in function ‘_dispatch_messages’
stonehearth/services/server/threads/thread.luac:128: in function <stonehearth/services/server/threads/thread.luac:123>
[C]: in function ‘suspend’
stonehearth/ai/actions/follow_path_action.luac:29: in function <stonehearth/ai/actions/follow_path_action.luac:7>
[C]: ?
[C]: ?
…
[C]: in function ‘run’
stonehearth/services/server/ai/compound_action.luac:133: in function <stonehearth/services/server/ai/compound_action.luac:129>
[C]: ?
[C]: ?
[C]: in function ‘run’
stonehearth/components/ai/ai_component.luac:190: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
Page 3:
develop-2650 (x64)bad frame trasition from “add_action” from "starting_thinking"stack traceback:
stonehearth/services/server/threads/thread.luac:87: in function <stonehearth/services/server/threads/thread.luac:87>
[C]: in function ‘fn’
stonehearth/services/server/threads/thread.luac:109: in function ‘private_msg’
stonehearth/services/server/threads/thread.luac:168: in function ‘_dispatch_messages’
stonehearth/services/server/threads/thread.luac:128: in function ‘suspend’
stonehearth/services/server/threads/thread.luac:146: in function ‘sleep_realtime’
stonehearth/components/ai/ai_component.luac:191: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
After the error, my hearthlings where frozen. So I closed the game entirely and reloaded de save data.
After doing so, I got this message.
Page 1:
develop-2650 (x64)stonehearth/services/server/ai/ai_service.luac:116: error in args passed to should_start_thinking: missing argument “ghost” of type “userdata: 0000005294113B48” in “[u:7960 place plantable item]”.stack traceback:
[C]: ?
[C]: in function ‘error’
stonehearth/services/server/ai/ai_service.luac:116: in function ‘report_error’
stonehearth/services/server/ai/ai_service.luac:148: in function <stonehearth/services/server/ai/ai_service.luac:103>
[C]: in function ‘start_thinking’
…onehearth/services/server/tasks/run_task_action.luac:26: in function ‘_start_stop_thinking’
…onehearth/services/server/tasks/run_task_action.luac:50: in function <…onehearth/services/server/tasks/run_task_action.luac:48>
[C]: in function ‘start_thinking’
stonehearth/services/server/ai/compound_action.luac:86: in function ‘_start_thinking_on_frame’
stonehearth/services/server/ai/compound_action.luac:74: in function <stonehearth/services/server/ai/compound_action.luac:61>
[C]: in function ‘start_thinking’
stonehearth/services/server/ai/compound_action.luac:86: in function ‘_start_thinking_on_frame’
stonehearth/services/server/ai/compound_action.luac:74: in function <stonehearth/services/server/ai/compound_action.luac:61>
[C]: ?
[C]: in function ‘run’
stonehearth/components/ai/ai_component.luac:190: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
Page 2
develop-2650 (x64)stonehearthstack traceback:
[C]: in function ‘start_thinking’
…onehearth/services/server/tasks/run_task_action.luac:26: in function ‘_start_stop_thinking’
…onehearth/services/server/tasks/run_task_action.luac:50: in function <…onehearth/services/server/tasks/run_task_action.luac:48>
[C]: in function ‘start_thinking’
stonehearth/services/server/ai/compound_action.luac:86: in function ‘_start_thinking_on_frame’
stonehearth/services/server/ai/compound_action.luac:74: in function <stonehearth/services/server/ai/compound_action.luac:61>
[C]: in function ‘start_thinking’
stonehearth/services/server/ai/compound_action.luac:86: in function ‘_start_thinking_on_frame’
stonehearth/services/server/ai/compound_action.luac:74: in function <stonehearth/services/server/ai/compound_action.luac:61>
[C]: ?
[C]: in function ‘run’
stonehearth/components/ai/ai_component.luac:190: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
Page 3:
develop-2650 (x64)bad frame trasition from “stop” from "starting_thinking"stack traceback:
[C]: ?
[C]: in function ‘stop’
stonehearth/components/ai/ai_component.luac:194: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
Page 4:
develop-2650 (x64)invalid initial state “starting_thinking” in runstack traceback:
[C]: ?
[C]: in function ‘run’
stonehearth/components/ai/ai_component.luac:190: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>
Page 5:
develop-2650 (x64)stonehearth/services/server/ai/ai_service.luac:116: error in args passed to start_thinking: missing argument “ghost” of type “userdata: 0000005294113B48” in “[u:13291 place an item]”.stack traceback:
[C]: ?
[C]: in function ‘error’
stonehearth/services/server/ai/ai_service.luac:116: in function ‘report_error’
stonehearth/services/server/ai/ai_service.luac:148: in function <stonehearth/services/server/ai/ai_service.luac:103>
[C]: in function ‘start_thinking’
…onehearth/services/server/tasks/run_task_action.luac:26: in function ‘_start_stop_thinking’
…onehearth/services/server/tasks/run_task_action.luac:50: in function <…onehearth/services/server/tasks/run_task_action.luac:48>
[C]: in function ‘start_thinking’
stonehearth/services/server/ai/compound_action.luac:86: in function ‘_start_thinking_on_frame’
stonehearth/services/server/ai/compound_action.luac:74: in function <stonehearth/services/server/ai/compound_action.luac:61>
[C]: in function ‘start_thinking’
stonehearth/services/server/ai/compound_action.luac:86: in function ‘_start_thinking_on_frame’
stonehearth/services/server/ai/compound_action.luac:74: in function <stonehearth/services/server/ai/compound_action.luac:61>
[C]: ?
[C]: in function ‘run’
stonehearth/components/ai/ai_component.luac:190: in function ‘_thread_main’
stonehearth/services/server/threads/thread.luac:90: in function <stonehearth/services/server/threads/thread.luac:89>
[C]: in function ‘xpcall’
stonehearth/services/server/threads/thread.luac:89: in function ‘f’
radiant/lib/env.luac:8: in function <radiant/lib/env.luac:8>

