select_all_geometry

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

With no annotations, the description carries the full burden. It does disclose that this mutates selection state inside a mesh and that it returns counts of what ended up selected, which is useful. However it never states prerequisites such as whether the mesh must be in edit mode or active, nor what happens if the named object is not a mesh or does not exist, and TOGGLE vs INVERT semantics are left unexplained.

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?

Front-loaded lead sentence, then a short disambiguation clause, then Args and Returns blocks. Every line carries information and nothing is padded.

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?

For a two-parameter selection tool with an output schema, this covers purpose, sibling routing, both parameters, and the return shape. It is only short of complete in that no edit-mode/context prerequisite or error behavior is mentioned before an agent commits to calling it.

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 coverage is 0%, so the description must compensate, and it does: object_name is described as the name of the mesh object (adding the mesh-type constraint) and all four allowed action values are enumerated. The remaining gap is that INVERT and TOGGLE are listed side by side with no explanation of how they differ, leaving the agent to guess between two similar-sounding modes.

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?

States a specific verb set (select/deselect/invert), a specific resource (all vertices, edges and faces) and a specific scope (one mesh). It also explicitly contrasts with select_objects, so an agent can distinguish it from the object-level sibling without opening either schema.

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?

"Acts inside a mesh. To select whole objects in the scene, use select_objects." names the alternative and the exact condition that selects it. The four action values further tell the agent which mode variants exist.

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