Error in synthesis with parameter passing into primitive template

[gcampax]

If there is an action primitive template that allows parameter passing, we get an error like this in synthesis:

monitorable list query image_search(in req query : String
                                    #_[canonical={
                                      base=["search query", "query"],
                                      passive_verb=["matching #", "containing #", "about #"],
                                      adjective=["#"]
                                    }]
                                    #_[prompt=["what do you want to search", "what are you looking for"]]
                                    #[string_values="tt:search_query"],
                                    out height : Number
                                    #_[prompt="what height are you looking for ( in pixels )"]
                                    #_[canonical={
                                      base=["height", "image height"],
                                      adjective=["# tall", "# pixels tall", "# pixels high"]
                                    }]
                                    #[min_number=1])
#_[canonical=["images", "pictures", "photo"]]
#_[confirmation="images matching $query from Bing"]
#_[result=["here is an image for you", "here is what i found"]]
#_[formatted=[{
  type="rdl",
  webCallback="${link}",
  displayTitle="${title}",
  pictureUrl="${picture_url}"
}]]
#[minimal_projection=["title", "link", "picture_url"]]
#[poll_interval=3600000ms]
#[doc="search for `query` on Bing Images"]; title
Error expanding rule NT[thingpedia_complete_join_action_past] -> turned to ${p_brt} your light bulb brightness (NT[p_brt : ctx_current_query])
Minibatch took 63 seconds and produced 0 dialogues

(the "title" property is gone from the schema but we don't notice, maybe something is not honoring #[minimal_projection])