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locate_gate_defects

Read-only

Find where a 3D model fails validity checks, returning defect coordinates and repair hints to fix exact edges or faces instead of guessing.

Instructions

Report WHERE a solid fails the validity gate, with 3D coordinates — so you can fix the exact edge/face instead of guessing. validate()/export() tell you WHAT is wrong (e.g. "1 non-manifold edge", "BRepCheck failed") but not where; call this when validate() FAILs to get a per-defect list: brep_invalid_face (face index + center + BRepCheck status, e.g. an unorientable BSpline), open_edge / nonmanifold_edge (B-rep edge midpoint + faces_incident), the mesh self-touches strict CAD/mesh consumers reject — mesh_nonmanifold_edge (edge midpoint) and mesh_nonmanifold_vertex (corner-to-corner touch point), mesh_untriangulated_face (a face that cannot tessellate at the base tolerance), mesh_refined_untriangulated_face (a face that only fails at a finer tolerance) — and mesh_vertex_deflection_defect (a tessellated edge endpoint that misses its own BREP vertex by more than the mesh deflection — a patched/healed face whose boundary is topologically closed but geometrically off-vertex; BRepCheck and even the open-edge count can both read clean, but a strict mesh sanity check still rejects it). Each defect includes a generic repair hint plus diagnostic_class / repair_family / next_step metadata; the top-level diagnosis block counts defect kinds and recommends the next verification path. An empty list means the part passes the structural checks. Bounded out-of-process (it mesh-checks), so a huge part returns a clean budget error rather than hanging. object_name: named object from show() (default: current shape).

Input Schema

TableJSON Schema

Name	Required	Description	Default
`object_name`	No

Output Schema

TableJSON Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Addedv0.3.59Jun 25, 2026

TDQS

A4.9/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Even though readOnlyHint=true already marks this as read-only, the description adds significant behavioral context beyond annotations: it is bounded out-of-process, mesh-checks, and returns a clean budget error for huge parts instead of hanging. It also discloses the output structure (per-defect metadata, diagnosis block, repair hints) and the empty-list meaning. No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The purpose is front-loaded and every sentence adds a distinct piece of information: when to use, the defect taxonomy, budget behavior, and parameter semantics. However, the long single block of defect types is dense and could be broken into scannable sections; the length is justified but the structure is not ideal.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only diagnostic with an output schema present, the description is complete: it covers invocation condition, output granularity, coordinate types, pass/fail interpretation, budget-limit behavior, and parameter semantics. Because an output schema exists, the description does not need to restate return values. Nothing essential is missing for an agent to select and invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description carries the full burden for parameters. It fully compensates by explaining the only parameter: 'object_name: named object from show() (default: current shape)'. This clarifies both where the value comes from and its default, which is more than the schema's bare default of '' provides.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb and resource: 'Report WHERE a solid fails the validity gate, with 3D coordinates'. It explicitly contrasts with validate()/export(), which tell WHAT is wrong but not where, so an agent can distinguish it from sibling tools. This is a clear, non-tautological purpose statement.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives an explicit trigger: 'call this when validate() FAILs to get a per-defect list'. It names the alternatives (validate()/export()) and explains what those alternatives lack. It also clarifies the pass condition ('An empty list means the part passes the structural checks'), which helps the agent interpret the result and decide next steps.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.