get_mesh_stats

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

readOnlyHint=true and openWorldHint=false already tell the agent this is a safe, local read. The description's claim that it "returns per-mesh breakdown and totals" is largely redundant with the output schema. It says nothing about how non-mesh prims or empty subtrees are handled, or about cost on large subtrees.

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?

Three short lines, front-loaded with the core capability. The closing "etc." is mild filler but does not undermine the structure.

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 single-parameter read tool with annotations and an output schema, the description covers purpose, scope, and intended use. Only the sibling disambiguation from get_prim_face_count_tree and non-mesh prim handling are missing.

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?

Only one parameter, and the schema covers it at 100% coverage, including the note that descendant meshes are included. The description's "prim or subtree" matches the schema without adding new semantics, so the baseline of 3 is right.

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 and resource: counts of faces, vertices and triangles for a prim or its subtree. That is concrete enough to act on. It does not differentiate itself from the close sibling get_prim_face_count_tree, so an agent comparing the two still has to guess.

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?

"Use for measuring geometry budget, shell reduction ratios" gives concrete motivating scenarios, which is more than most definitions. It stops short of exclusions or naming an alternative, so the overlap with get_prim_face_count_tree is left unresolved.

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