mesh-select_by_index

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

No annotations are provided, so the description carries full burden. It doesn't disclose whether the selection replaces, adds, removes, or toggles (though the 'action' parameter covers this), nor does it mention side effects like deselecting other elements, mode requirements, or whether the operation is destructive. The description is minimal and lacks behavioral context beyond the basic action.

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

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

The description is a single concise sentence, front-loaded with the core purpose. No wasted words, but it may be too terse given the lack of parameter details.

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

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

With 4 parameters, 0% schema coverage, no annotations, and no output schema, the description is insufficient. It doesn't explain how indices are formatted (comma-separated is in schema but not description), what modes are available, or what the tool returns. The tool is moderately complex (selection actions, element modes) and the description doesn't cover these aspects.

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

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

Schema description coverage is 0%, so the description must compensate. It only mentions 'zero-based index' which relates to the 'indices' parameter, but doesn't explain 'mode' (VERT/EDGE/FACE), 'action' (REPLACE/ADD/REMOVE/TOGGLE), or 'object' semantics. The description adds minimal value beyond the schema's titles and enums.

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

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

The description 'Select mesh elements by zero-based index' clearly states the action (select) and resource (mesh elements) with a specific detail (zero-based index). It distinguishes from sibling tools like mesh-select_all and mesh-selection_report, though it doesn't explicitly name them.

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

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

No guidance on when to use this tool versus alternatives like mesh-select_all or mesh-selection_report. The description implies usage for selecting specific elements by index but doesn't provide context on prerequisites (e.g., object must be in edit mode) or when to prefer other selection tools.

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