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diff --git a/kamon-annotation/src/main/java/kamon/annotation/Segment.java b/kamon-annotation/src/main/java/kamon/annotation/Segment.java
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+/*
+ * =========================================================================================
+ * Copyright © 2013-2015 the kamon project <http://kamon.io/>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+
+package kamon.annotation;
+
+import java.lang.annotation.*;
+
+/**
+ * A marker annotation to start a new Segment.
+ * <p>
+ * <p>
+ * Given a method like this:
+ * <pre><code>
+ *     {@literal @}Segment("coolSegmentName", tags="${'my-cool-tag':'my-cool-value'}")
+ *     public String coolName(String name) {
+ *         return "Hello " + name;
+ *     }
+ * </code></pre>
+ * <p>
+ * <p>
+ * A new Segment will be created only if in the moment of the method execution exist a TraceContext.
+ */
+@Documented
+@Target(ElementType.METHOD)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Segment {
+
+    /**
+     * @return The Segment's name.
+     * <p>
+     * Also, the Segment name can be resolved with an EL expression that evaluates to a String:
+     * <p>
+     * <pre>
+     * {@code
+     *  class Segment {
+     *        private long id;
+     *
+     *        public long getId() { return id; }
+     *
+     *        {@literal @}Segment (name = "${'segmentID:' += this.id}")
+     *        void segment() {} // create a Segment with name => segmentID:[id]
+     *    }
+     * }
+     * </pre>
+     */
+    String name();
+
+    /**
+     * @return The Segment's category.
+     */
+    String category();
+
+    /**
+     * @return The Segment's library.
+     */
+    String library();
+
+    /**
+     * Tags are a way of adding dimensions to metrics,
+     * these are constructed using EL syntax e.g. "${'algorithm':'1','env':'production'}"
+     *
+     * @return the tags associated to the segment
+     */
+    String tags() default "";
+}