Token-Efficient and Consistent AI Code Generation Through GNU Unified Diff (XML)

gnu-unified-diff-prompt.xml

<output>
  <OUTPUT_FORMAT>
    <type>JSON</type>
    <encoding>UTF-8</encoding>
    <structure>
      <target_file>string (relative path with forward slashes)</target_file>
      <diff>string (unified diff with \n line breaks)</diff>
      <error>string (optional, only present for errors)</error>
    </structure>
  </OUTPUT_FORMAT>
  <DIFF_SPECIFICATIONS>
    <headers>
      <format>
        <item>--- a/&lt;path&gt;</item>
        <item>+++ b/&lt;path&gt;</item>
      </format>
      <rules>
        <item>No timestamps/metadata</item>
        <item>Use a/ and b/ prefixes</item>
      </rules>
    </headers>
    <hunks>
      <format>@@ -&lt;start&gt;,&lt;count&gt; +&lt;start&gt;,&lt;count&gt; @@</format>
      <context>3 lines context before/after changes</context>
      <line_endings>LF (\n) line endings only</line_endings>
      <line_markers>
        <context> </context>
        <deletion>-</deletion>
        <addition>+</addition>
      </line_markers>
    </hunks>
    <special_cases>
      <new_file>
        <original>--- a/dev/null</original>
        <new>+++ b/&lt;relative_path&gt;</new>
      </new_file>
      <deleted_file>
        <original>--- a/&lt;relative_path&gt;</original>
        <new>+++ b/dev/null</new>
      </deleted_file>
    </special_cases>
  </DIFF_SPECIFICATIONS>
  <VALIDATION_RULES>
    <max_total_lines>10000</max_total_lines>
    <max_line_length>10000</max_line_length>
    <encoding>UTF-8 required</encoding>
    <rules>
      <item>No directory traversal</item>
      <item>Sanitized file paths</item>
      <item>No binary files</item>
      <item>Within project scope</item>
    </rules>
  </VALIDATION_RULES>
  <EXAMPLES>
    <example>
      <description>Modification</description>
      <output>{"target_file":"src/example.js","diff":"--- a/src/example.js\n+++ b/src/example.js\n@@ -1,5 +1,5 @@\n function greet(name) {\n-  console.log(\"Hello, \" + name + \"!\");\n+  console.log(\"Hello, \" + name.toUpperCase() + \"!!!\");\n }\n \n greet(\"Alice\");\n"}</output>
    </example>
    <example>
      <description>Creation</description>
      <output>{"target_file":"src/newfile.js","diff":"--- a/dev/null\n+++ b/src/newfile.js\n@@ -0,0 +1,3 @@\n+console.log(\"This is a new file.\");\n"}</output>
    </example>
    <example>
      <description>Deletion</description>
      <output>{"target_file":"src/obsolete.js","diff":"--- a/src/obsolete.js\n+++ b/dev/null\n@@ -1,3 +0,0 @@\n-console.log(\"This file is obsolete.\");\n"}</output>
    </example>
  </EXAMPLES>
  <ERROR_HANDLING>
    <conditions>
      <item>Invalid/nonexistent file</item>
      <item>Binary file</item>
    </conditions>
    <responses>
      <error_example>{"target_file":"src/nonexistent.js","error":"Target file does not exist."}</error_example>
      <error_example>{"target_file":"assets/image.png","error":"Binary files are not supported."}</error_example>
    </responses>
  </ERROR_HANDLING>
  <SECURITY_REQUIREMENTS>
    <path_handling>
      <item>Sanitize all file paths</item>
      <item>Prevent directory traversal</item>
    </path_handling>
    <content_safety>
      <item>No code injection vectors</item>
      <item>Within allowed directory scope</item>
      <item>Valid JSON parsing guaranteed</item>
    </content_safety>
  </SECURITY_REQUIREMENTS>
</output>