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xml-standards

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XML tag structure patterns for Claude Code agents and commands. Use when designing or implementing agents to ensure proper XML structure following Anthropic best practices.

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Source SKILL.md: https://github.com/MadAppGang/claude-code/blob/HEAD/plugins/agentdev/skills/xml-standards/SKILL.md

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plugin: agentdev updated: 2026-01-20

XML Tag Standards

Core Tags (Required for ALL Agents/Commands)

<role>

Defines agent identity and purpose.

<role>
  <identity>Expert [Domain] Specialist</identity>
  <expertise>
    - Core skill 1
    - Core skill 2
    - Core skill 3
  </expertise>
  <mission>
    Clear statement of what this agent accomplishes
  </mission>
</role>

<instructions>

Defines behavior constraints and workflow.

<instructions>
  <critical_constraints>
    <constraint_name>
      Description of critical rule that must be followed
    </constraint_name>
    <todowrite_requirement>
      You MUST use Tasks to track workflow progress.
    </todowrite_requirement>
  </critical_constraints>

  <core_principles>
    <principle name="Name" priority="critical|high|medium">
      Description of principle
    </principle>
  </core_principles>

  <workflow>
    <phase number="1" name="Phase Name">
      <step>Step description</step>
      <step>Step description</step>
    </phase>
  </workflow>
</instructions>

<knowledge>

Domain-specific best practices and templates.

<knowledge>
  <section_name>
    Best practices, patterns, or reference material
  </section_name>
  <templates>
    <template name="Template Name">
      Template content
    </template>
  </templates>
</knowledge>

<examples>

Concrete usage scenarios (2-4 required).

<examples>
  <example name="Descriptive Name">
    <user_request>What user asks for</user_request>
    <correct_approach>
      1. Step one
      2. Step two
      3. Step three
    </correct_approach>
  </example>
</examples>

<formatting>

Communication style and output format.

<formatting>
  <communication_style>
    - Style guideline 1
    - Style guideline 2
  </communication_style>
  <completion_message_template>
    Template for completion messages
  </completion_message_template>
</formatting>

Specialized Tags by Agent Type

Orchestrators (Commands)

<orchestration>
  <allowed_tools>Task, Bash, Read, TaskCreate, TaskUpdate, TaskList, TaskGet, AskUserQuestion</allowed_tools>
  <forbidden_tools>Write, Edit</forbidden_tools>

  <delegation_rules>
    <rule scope="design">ALL design → architect agent</rule>
    <rule scope="implementation">ALL implementation → developer agent</rule>
    <rule scope="review">ALL reviews → reviewer agent</rule>
  </delegation_rules>

  <phases>
    <phase number="1" name="Phase Name">
      <objective>What this phase achieves</objective>
      <steps>
        <step>Step description</step>
      </steps>
      <quality_gate>Exit criteria for this phase</quality_gate>
    </phase>
  </phases>
</orchestration>

<error_recovery>
  <strategy>
    Recovery steps for common failures
  </strategy>
</error_recovery>

Planners (Architects)

<planning_methodology>
  <approach>How planning is performed</approach>
  <deliverables>What planning produces</deliverables>
</planning_methodology>

<gap_analysis>
  <checklist>Items to verify during planning</checklist>
</gap_analysis>

<output_structure>
  <format>Structure of planning output</format>
</output_structure>

Implementers (Developers)

<implementation_standards>
  <file_writing_standards>
    <standard name="Standard Name">Description</standard>
  </file_writing_standards>

  <quality_checks mandatory="true">
    <check name="check_name" order="1">
      <tool>Tool name</tool>
      <command>Command to run</command>
      <requirement>What must pass</requirement>
      <on_failure>Recovery action</on_failure>
    </check>
  </quality_checks>

  <validation_checks>
    <check order="1" name="Check Name">
      Validation criteria
    </check>
  </validation_checks>
</implementation_standards>

Reviewers

<review_criteria>
  <focus_areas>
    <area name="Area Name" priority="critical|high|medium" weight="20%">
      **Check:**
      - Item to verify
      - Item to verify

      **Common Issues:**
      - Issue description

      **Critical if**: Condition for critical severity
      **High if**: Condition for high severity
    </area>
  </focus_areas>

  <feedback_format>
    Template for review feedback
  </feedback_format>
</review_criteria>

<approval_criteria>
  <status name="PASS">Criteria for passing</status>
  <status name="CONDITIONAL">Criteria for conditional approval</status>
  <status name="FAIL">Criteria for failure</status>
</approval_criteria>

Testers

<testing_strategy>
  <approach>Testing methodology</approach>
  <test_types>
    <type name="Type Name">Description</type>
  </test_types>
</testing_strategy>

<coverage_requirements>
  <requirement>Coverage criteria</requirement>
</coverage_requirements>

Nesting Rules

  1. Proper Hierarchy - Tags must be properly nested
  2. Closing Tags - All opening tags must have closing tags
  3. Semantic Attributes - Use name, priority, order attributes
  4. Consistent Naming - Use lowercase-with-hyphens for tag names

Code Blocks in XML

<template name="Example">
```language
// code here - note: opening ``` directly under tag

Character Escaping

Only in XML attribute values and text nodes (NOT in code blocks):

  • &lt; for <
  • &gt; for >
  • &amp; for &