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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description still earns credit by disclosing the authorization requirement and the exact refusal behavior, which no annotation conveys. It stops short of describing pagination or response shape.

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?

Two sentences, front-loaded with the resource definition and followed by the access constraint. The component list is a slight enumeration tax but doubles as a useful content preview, so it earns its place.

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 no output schema, the description does well to enumerate what the BOM contains. However, blocks_only is left undefined and there is no disambiguation from the mechanical_get_robot sibling, so an agent could still call the wrong tool or pass the wrong flag.

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 bears the full burden and does not meet it. It never mentions robot_id explicitly as the selector, and blocks_only — a boolean filter that materially changes the output — is completely unexplained in both schema and description.

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?

Names a specific resource (mechanical bill of materials for one robot) and enumerates its components, so an agent knows exactly what comes back. It does not, however, distinguish itself from the sibling mechanical_get_robot, which an agent could reasonably assume returns something similar.

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?

The description supplies a prerequisite (access right on the requested robot) and the failure mode (refusal naming the robot), which is genuinely actionable. But it never says when to pick this over mechanical_get_robot, hardware_get_robot_hardware, or mechanical_get_block_analysis — the agent must infer that from the tool name alone.

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