--- a/spec/latest/json-ld-api/index.html	Wed Dec 19 14:52:50 2012 +0100
+++ b/spec/latest/json-ld-api/index.html	Wed Dec 19 15:10:27 2012 +0100
@@ -2091,17 +2091,15 @@
   <section>
     <h3>Callbacks</h3>
 
-    <p class="issue" data-number="153">Developers should note that the details of
-      error handling are being actively debated.</p>
-
     <p>JSON-LD processors utilize callbacks in order to return information in an
       asynchronous manner to calling applications. This section details the
       parameters sent to those callbacks.</p>
 
     <section>
       <h3>JsonLdCallback</h3>
-      <p>The JsonLdCallback is used to return a processed JSON-LD
-        representation as the result of processing an API method.</p>
+      <p>The <a>JsonLdCallback</a> is called when processing of an API method
+        of <a>JsonLdProcessor</a> has been completed successfully or been
+        terminated by an error.</p>
 
       <dl title="callback JsonLdCallback = void" class="idl">
         <dt>JsonLdProcessingError error</dt>
@@ -2163,26 +2161,21 @@
 
     <section>
       <h3>JsonLdProcessingError</h3>
-      <p>The JsonLdProcessingError type is used to encapsulate a variety of
-      parameters that outline the cause of a particular
-      <a>JsonLdProcessor</a> error.</p>
+
+      <p class="issue" data-number="153">Developers should note that the details of
+        error handling are being actively debated.</p>
+
+      <p>The <a>JsonLdProcessingError</a> type is used to report errors to a
+        <a>JsonLdCallback</a>.</p>
 
       <dl title="dictionary JsonLdProcessingError" class="idl">
         <dt>JsonLdErrorCode code</dt>
         <dd>a string representing the particular error type, as described in
           the various algorithms in this document.</dd>
-        <dt>DOMString operation</dt>
-        <dd>a string representing the operation that was being performed
-          when the conformance issue was raised. Valid values for the
-          string include <code>compact</code>, and <code>expand</code>.</dd>
-        <dt>object or object[] source</dt>
-          <dd>An object reference to the original JSON-LD document being
-          processed.</dd>
-        <dt>DOMString sourceKey</dt>
-          <dd>The key value associated with the value that triggered the
-          conformance issue.</dd>
-        <dt>any or any[] sourceValue</dt>
-          <dd>The value that triggered the conformance issue.</dd>
+        <dt>DOMString? message</dt>
+        <dd>an optional error message containing additional debugging information.
+          The specific contents of error messages are outside the scope of this
+          specification and thus implementation dependent.</dd>
       </dl>
     </section>