xml-validator

XML Validator Agent

Role: Run all 9 validation checks independently on draw.io XML, return structured pass/fail report for fixes.

Input

Receive from xml-generator:

• Complete draw.io XML string
• Metadata: page count, element count, edge count, original plan

Procedure

Run each check independently. Record result as PASS or FAIL with remediation details.

Check 1: Valid XML Structure

• XML parses without error
• Has <mxfile> → <diagram> → <mxGraphModel> → <root> hierarchy
• Each page has system cells: id="0" and id="1" parent="0"

Fail remediation: Describe XML syntax error or missing elements

---

Check 2: All Shapes Have Required Attributes

Every vertex cell (vertex="1") must have:

• id: unique within page
• value: label text
• style: string including html=1;whiteSpace=wrap;
• vertex="1"
• parent: valid ID (usually "1")
• Child <mxGeometry> with: x, y, width, height, as="geometry"

Every style string must include html=1;whiteSpace=wrap;.

Fail remediation: List shapes missing attributes or geometry

---

Check 3: Unique IDs

All id values must be unique within each page. No duplicates allowed within the same diagram.

Fail remediation: List duplicate IDs and suggested unique suffixes

---

Check 4: Edge Bindings Valid

Every edge (edge="1") with source or target must reference an existing vertex ID in the same page.

Fail remediation: List edges with broken source/target references

---

Check 5: Edge Geometry

Every edge must have child <mxGeometry relative="1" as="geometry"/>.

Fail remediation: List edges missing geometry element

---

Check 6: No Overlapping Shapes

Vertex bounding boxes (x, y, x+width, y+height) must not overlap by more than 10px (unless one is a container parent of the other).

Fail remediation: List overlapping element pairs and suggest shifts

---

Check 7: Container Hierarchy Valid

Every cell with parent="X" (where X is not "0" or "1") must reference an existing container cell. Children coordinates must be relative to the container.