[go] Add attribute documentation.

--
MOS_MIGRATED_REVID=106918682
diff --git a/tools/build_rules/go/README.md b/tools/build_rules/go/README.md
index aa858ff..3db331c 100644
--- a/tools/build_rules/go/README.md
+++ b/tools/build_rules/go/README.md
@@ -1,5 +1,17 @@
 # Go rules
 
+<div class="toc">
+  <h2>Rules</h2>
+  <ul>
+    <li><a href="#go_prefix">go_prefix</a></li>
+    <li><a href="#go_library">go_library</a></li>
+    <li><a href="#go_binary">go_binary</a></li>
+    <li><a href="#go_test">go_test</a></li>
+  </ul>
+</div>
+
+## Overview
+
 The rules should be considered experimental. They support:
 
 * libraries
@@ -10,7 +22,7 @@
 They currently do not support (in order of importance):
 
 * Darwin
-* //+build tags
+* `//+build` tags
 * auto generated BUILD files.
 * C/C++ interoperation (cgo, swig etc.)
 * race detector
@@ -86,3 +98,187 @@
 ## Disclaimer
 
 These rules are not supported by Google's Go team.
+
+<a name="go_prefix"></a>
+## go\_prefix
+
+```python
+go_prefix(prefix)
+```
+
+<table class="table table-condensed table-bordered table-params">
+  <colgroup>
+    <col class="col-param" />
+    <col class="param-description" />
+  </colgroup>
+  <thead>
+    <tr>
+      <th colspan="2">Attributes</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <td><code>prefix</code></td>
+      <td>
+        <code>String, required</code>
+        <p>Global prefix used to fully quality all Go targets.</p>
+        <p>
+          In Go, imports are always fully qualified with a URL, eg.
+          <code>github.com/user/project</code>. Hence, a label <code>//foo:bar
+          </code> from within a Bazel workspace must be referred to as
+          <code>github.com/user/project/foo/bar</code>. To make this work, each
+          rule must know the repository's URL. This is achieved, by having all
+          go rules depend on a globally unique target that has a
+          <code>go_prefix</code> transitive info provider.
+        </p>
+      </td>
+    </tr>
+  </tbody>
+</table>
+
+<a name="go_library"></a>
+## go\_library
+
+```python
+go_library(name, srcs, deps, data)
+```
+<table class="table table-condensed table-bordered table-params">
+  <colgroup>
+    <col class="col-param" />
+    <col class="param-description" />
+  </colgroup>
+  <thead>
+    <tr>
+      <th colspan="2">Attributes</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <td><code>name</code></td>
+      <td>
+        <code>Name, required</code>
+        <p>A unique name for this rule.</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>srcs</code></td>
+      <td>
+        <code>List of labels, required</code>
+        <p>List of Go <code>.go</code> source files used to build the
+        library</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>deps</code></td>
+      <td>
+        <code>List of labels, optional</code>
+        <p>List of other libraries to linked to this library target</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>data</code></td>
+      <td>
+        <code>List of labels, optional</code>
+        <p>List of files needed by this rule at runtime.</p>
+      </td>
+    </tr>
+  </tbody>
+</table>
+
+<a name="go_binary"></a>
+## go\_binary
+
+```python
+go_binary(name, srcs, deps, data)
+```
+<table class="table table-condensed table-bordered table-params">
+  <colgroup>
+    <col class="col-param" />
+    <col class="param-description" />
+  </colgroup>
+  <thead>
+    <tr>
+      <th colspan="2">Attributes</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <td><code>name</code></td>
+      <td>
+        <code>Name, required</code>
+        <p>A unique name for this rule.</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>srcs</code></td>
+      <td>
+        <code>List of labels, required</code>
+        <p>List of Go <code>.go</code> source files used to build the
+        binary</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>deps</code></td>
+      <td>
+        <code>List of labels, optional</code>
+        <p>List of other libraries to linked to this binary target</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>data</code></td>
+      <td>
+        <code>List of labels, optional</code>
+        <p>List of files needed by this rule at runtime.</p>
+      </td>
+    </tr>
+  </tbody>
+</table>
+
+<a name="go_test"></a>
+## go\_test
+
+```python
+go_test(name, srcs, deps, data)
+```
+<table class="table table-condensed table-bordered table-params">
+  <colgroup>
+    <col class="col-param" />
+    <col class="param-description" />
+  </colgroup>
+  <thead>
+    <tr>
+      <th colspan="2">Attributes</th>
+    </tr>
+  </thead>
+  <tbody>
+    <tr>
+      <td><code>name</code></td>
+      <td>
+        <code>Name, required</code>
+        <p>A unique name for this rule.</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>srcs</code></td>
+      <td>
+        <code>List of labels, required</code>
+        <p>List of Go <code>.go</code> source files used to build the
+        test</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>deps</code></td>
+      <td>
+        <code>List of labels, optional</code>
+        <p>List of other libraries to linked to this test target</p>
+      </td>
+    </tr>
+    <tr>
+      <td><code>data</code></td>
+      <td>
+        <code>List of labels, optional</code>
+        <p>List of files needed by this rule at runtime.</p>
+      </td>
+    </tr>
+  </tbody>
+</table>