term_reference field is not created I set up the Services module as REST server, so I can create nodes with custom fields by REST client as in Services 3 - POST node.create with custom fields.

The settings of the Services module are the following.

Server =&gt; REST
Path to endpoint =&gt; "neoapi"
Session authentication =&gt; yes
Response formatters =&gt; json
Request parsing =&gt; application/json &amp; application/x-www-form-urlencoded
Resource path =&gt; http://127.0.0.1/neoapi/node

Content type =&gt; mycontent
Term reference field =&gt; Autocomplete term widget (tagging)


And post next JSON data via Google Chrome Advanced Rest Client

{     
"type":"mycontent",
"title":"The New Article",
"body":{
  "und":[ {
    "value":"This is the body of new article."
    } ] },
"field_neo_terms":{
  "und":[ {
    "tid":"3"
    } ] }
}


At REST client I receive "200. OK" NID and URI of new node. But in site i have new node with title and body, but without terms and error:

Warning: mb_strlen() expects parameter 1 to be string, array given in drupal_strlen()
(line 441 of C:\Program Files\VertrigoServ\www\includes\unicode.inc).
Warning: preg_match_all() expects parameter 2 to be string, array in   drupal_explode_tags()
(line 7254 of C:\Program Files\VertrigoServ\www\includes\common.inc).
Warning: array_unique() expects parameter 1 to be array, null given in drupal_explode_tags()
(line 7255 of C:\Program Files\VertrigoServ\www\includes\common.inc).
Warning: Invalid argument supplied for foreach() in drupal_explode_tags()
(line 7258 of C:\Program Files\VertrigoServ\www\includes\common.inc).
As the documentation you linked says, the structure for the fivestar field is the following.

{
  "field_fivestar":[{
    "rating":"100",
    "target":"0"
  }]
}


Probably you are missing "target"

Also, if you are using auto complete for taxonomy you should use the term id, tid, 3 times:

{
  "field_termins":[{
    "tid":{
      "tid":"[tid:26686]"
    }
   }]
}


Auto complete is the tricky part.