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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds two pieces of context the annotations do not carry: an authorization requirement tied to the specific robot, and the fact that only 'active' signals are returned (a filtering behavior, not a full history). Return shape and pagination remain unstated.

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 short sentences with zero filler: the purpose is stated first, then the access prerequisite. Nothing is repeated from the title or schema.

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?

It is a simple read-only tool with annotations covering the safety profile and no output schema to explain, which keeps the bar modest. However, with no output schema and 0% parameter coverage, the undefined include_global flag and the unstated notion of what a 'signal' contains leave real gaps for an agent about to call 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 description coverage is 0% for both parameters. The description hints that robot_id selects a single robot, but include_global (default true) is entirely unexplained — an agent cannot tell whether toggling it widens scope to fleet-wide signals or filters them out. With near-zero schema coverage, the description needed to compensate and does not.

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 gives a specific verb ('signals affecting') and a clearly bounded resource: one robot's mechanical BOM, with the adverb 'active' narrowing the result set. It implicitly separates itself from mechanical_list_signals by scope (single robot vs. list), but never names that sibling explicitly, so it sits just below the top tier.

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 only explicit guidance is a prerequisite: an access right on the requested robot. There is no statement of when to prefer this over mechanical_list_signals, hardware_get_robot_signals, or software_get_robot_signals, so the agent must infer from the domain prefix.

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