diff --git a/source/recipe.rst b/source/recipe.rst
index df29b4e..3bcc8e7 100644
--- a/source/recipe.rst
+++ b/source/recipe.rst
@@ -267,7 +267,8 @@ To assign synapse properties, the classification field needs to be set:
   .. note::
 
      The type has to start with either ``E`` for excitatory connections or
-     ``I`` for inhibitory connections.
+     ``I`` for inhibitory connections.  This legacy behavior may be overriden by
+     specifying the `connection_model` parameter for the `SynapsesClassification` section.
 
 Two optional attributes may be set:
 
@@ -318,7 +319,7 @@ property name:
 Truncated Normal distributions are limited to the central value ±σ and are
 re-rolled until positive values has been obtained.
 
-Two optional attributes can be specified, where each attribute will have to
+Three optional attributes can be specified, where each attribute will have to
 be given for all `SynapsesClassification` elements:
 
 - `gsynSRSF`, the scale factor for the conductance; `SRSF`: 'synaptic receptor scaling factor'
@@ -332,6 +333,9 @@ be given for all `SynapsesClassification` elements:
   where :math:`ca` denotes the simulated calcium concentration in
   millimolar and :math:`y` a scalar such that at
   :math:`ca = 2.0:\ u_\text{final} = u`. (Markram et al., 2015)
+- `connection_model`, to specify the filename stub (without a final extension) that should
+  appear in the field with the same name in the corresponding SONATA edge file.  Presence
+  of this attribute will suppress creating the `syn_type_id` field in the edge file.
 
 These attributes will be copied for each synapse corresponding to its
 classification.  If they are not specified, no corresponding columns will
diff --git a/source/sonata_tech.rst b/source/sonata_tech.rst
index 8d09f6f..5333507 100644
--- a/source/sonata_tech.rst
+++ b/source/sonata_tech.rst
@@ -288,10 +288,11 @@ Group column represents the HDF group where the dataset is located under /<popul
                                                                        where :math:`ca` denotes the simulated calcium concentration in
                                                                        millimolar and :math:`y` a scalar such that at :math:`ca = 2.0:\ u_\text{final} = u`. (Markram et al., 2015)
 
-    /0            ``syn_type_id``               uint32     Mandatory   Takes the value 0 for inhibitory synapses, 100 for excitatory synapses (numerical values due to historic reasons)
+    /0            ``syn_type_id``               uint32     Mandatory   Takes the value 0 for inhibitory synapses, 100 for excitatory synapses (numerical values due to historic reasons).  Deprecated, replaced by ``connection_model``.
+    /0            ``connection_model``          uft8       Mandatory   Template or class of the model for the edge, should be an stored as an enumeration in the `@library` group.
     /0            ``syn_property_rule``         uint32     Mandatory   The position of the rule that leads to the synapse in the recipe
     /0            ``delay``                     float32    Mandatory   The axonal delay (in ms, ``NaN`` for dendro-dendritic synapses).
-    /0/@library   ``spine_morphology``          utf8       Optional    Spine morphology file relative path, without the file extension.
+    /0            ``spine_morphology``          utf8       Optional    Spine morphology file relative path, without the file extension. Should be stored as an enumeration in the `@library` group.
                                                                        Example "mymorphology" or "mypath/mymorphology". Set to an empty string if synapse forms on the shaft.
     /             ``edge_type_id``              int64      Mandatory   Links an edge to the underlying CSV file; not used at BBP.
     /             ``source_node_id``            uint64     Mandatory   The id of the presynaptic neuron.