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

Annotations already declare idempotentHint=true and destructiveHint=true, so 'Idempotent' in the description repeats structured data. 'Free' adds genuinely new cost/quota context absent from annotations, but the description does not clarify that unwatching destroys no underlying company data despite the destructive hint.

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, front-loaded clauses with zero waste; the operation is stated first and qualifying traits follow.

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 simple two-required-param mutation with no output schema, the essentials are present, but it omits how the watch is identified/confirmed and does not reconcile the destructive hint with this being a harmless reversible preference change.

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 100% and both parameters are fully documented with enum and identifier-format detail, so the schema carries the burden. The description adds nothing about the country/regNo pair.

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 ('Stop watching a company'), which is unambiguously the inverse of the sibling watch_company. It doesn't explicitly name that sibling, but the naming symmetry makes the distinction obvious.

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?

Usage is implied by the operation: you call it when you no longer want to track a company. There is no explicit when-to-use/when-not guidance, no mention of prerequisites (must the company already be watched?) or of how to find currently watched companies via list_watched.

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