xml-comparator

XML Comparator

Compare actual XML against an expected template using the validate-xml MCP tool (simple-data-comparator-mcp server).

Workflow

1. Discover the tool — call GetMcpTools for the comparator MCP server, then invoke validate-xml.
2. Prepare strings — pass full XML documents as plain strings in actual and template.
3. Call the tool — no optional parameters.
4. Check isError:
   • false → validation passed
   • true → parse difference lines and map paths back to elements/attributes
5. Report element paths, attribute names, and expected vs actual values clearly.

Parameters

Parameter	Required	Purpose
actual	yes	XML string to validate
template	yes	Expected XML template string

Interpreting results

Pass: Validation passed.

Fail:

Validation failed.
Differences:
[value_mismatch] catalog.book[0].title: expected "A", got "B"
[missing_element] root.child: expected element is missing
[extra_element] root.unexpected: unexpected extra element
[type_mismatch] root: expected array, got object
[array_length] items: expected 2 items, got 3
[parse_error] ...

Paths use dot notation; repeated elements use [index]. Attributes are included in comparison.

Example call

{
  "actual": "<root><value>42</value></root>",
  "template": "<root><value>42</value></root>"
}

Rules

• Pass the full XML fragment you want compared (envelope, body, or subtree — be consistent on both sides).
• Whitespace inside text nodes may affect comparison — normalize formatting when comparing text-heavy XML.
• Use validate-xml for XML — not validate-text or validate-json.
• DOCTYPE and XML declarations are ignored during parsing.
• On [parse_error], fix malformed XML before retrying.

Full reference

See references/xml-comparator.md for extended examples.