diff --git a/README.md b/README.md
new file mode 100644
index 0000000..90af278
--- /dev/null
+++ b/README.md
@@ -0,0 +1,19 @@
+![GSI Logo](http://gsi.dit.upm.es/templates/jgsi/images/logo.png)
+[EUROSENTIMETN Endpoint example](http://eurosentiment-resources.herokuapp.com) 
+=========================================
+Example endpoint that yields results compatible with the EUROSENTIMENT format and exposes the NIF API.
+It can be used as a template to adapt existing services to EUROSENTIMENT or to create new services.
+
+[DEMO on Heroku](http://eurosentiment-endpoint.herokuapp.com)
+
+This endpoint serves as bootcampt for any developer wishing to build applications that use the EUROSENTIMENT services.
+
+Acknowledgement
+---------------
+EUROSENTIMENT PROJECT
+Grant Agreement no: 296277
+Starting date: 01/09/2012
+Project duration: 24 months
+
+![Eurosentiment Logo](logo_grande.png)
+![FP7 logo](logo_fp7.gif)
diff --git a/app.py b/app.py
index dd487c5..78e3947 100644
--- a/app.py
+++ b/app.py
@@ -19,17 +19,21 @@ Simple Sentiment Analysis server for EUROSENTIMENT
 
 This class shows how to use the nif_server module to create custom services.
 '''
+import config
+import re
 from flask import Flask
 from random import random
 from nif_server import *
-import config
 
 app = Flask(__name__)
 
+rgx = re.compile("(\w[\w']*\w|\w)", re.U)
+
 def hard_analysis(params):
     response = basic_analysis(params)
     response["analysis"][0]["marl:algorithm"] = "SimpleAlgorithm"
     for i in response["entries"]:
+        contextid = i["@id"]
         polValue = random()
         if polValue > 0.5:
             pol = "marl:Positive"
@@ -41,6 +45,15 @@ def hard_analysis(params):
                           "marl:hasPolarity": pol
 
                           }]
+        i["strings"] = []
+        for m in rgx.finditer(i["nif:isString"]):
+            i["strings"].append({
+                "@id": "{}#char={},{}".format(contextid, m.start(), m.end()),
+                "nif:beginIndex": m.start(),
+                "nif:endIndex": m.end(),
+                "nif:anchorOf": m.group(0)
+            })
+
     return response
 
 app.analyse = hard_analysis
diff --git a/nif_server.py b/nif_server.py
index a6266ec..af9c5eb 100644
--- a/nif_server.py
+++ b/nif_server.py
@@ -43,7 +43,6 @@ PARAMS = {"input": {"aliases": ["i", "input"],
                         "options": ["json-ld"],
                         },
           "language": {"aliases": ["language", "l"],
-                       "default": None,
                        "required": False,
                        "options": ["es", "en"],
                        },
@@ -88,7 +87,11 @@ def get_params(req):
     return outdict
 
 def basic_analysis(params):
-    response = {"@context": "http://demos.gsi.dit.upm.es/eurosentiment/static/context.jsonld",
+    response = {"@context": ["http://demos.gsi.dit.upm.es/eurosentiment/static/context.jsonld",
+                             {
+                                 "@base": "{}#".format(request.url.encode('utf-8'))
+                             }
+                             ],
                 "analysis": [{
                     "@type": "marl:SentimentAnalysis"
                 }],
@@ -96,8 +99,9 @@ def basic_analysis(params):
                 }
     if "language" in params:
         response["language"] = params["language"]
-    for sentence in params["input"].split("."):
+    for idx, sentence in enumerate(params["input"].split(".")):
         response["entries"].append({
+            "@id": "Sentence{}".format(idx),
             "nif:isString": sentence
         })
     return response