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

Annotations already declare readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds meaningful context beyond them: the data source is Perplexity responses and the comparison is competitor citations versus your own, which tells the agent what the result set represents. It does not mention prerequisites (e.g. competitors needing to be configured) or latency.

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?

A single front-loaded sentence that states the operation, the discriminating condition, and the value proposition with no redundant wording.

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?

An output schema exists and the sole parameter is documented, so the description only needs to convey what the tool computes and why it matters, which it does. The one gap is the implicit prerequisite of having competitors tracked, which an agent would need to know before calling.

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?

With a single parameter at 100% schema description coverage ('Max results (1-50, default 20)'), the schema fully documents the input and the description adds no further meaning about limit behavior or ranking of results. Baseline 3 applies since the schema does the heavy lifting.

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 and resource ('Identify domains that cite your competitors... but not you') and states the selection logic, which distinguishes it from siblings like list_missed_citations or list_competitors. It never names an alternative explicitly, but the analytical framing makes the tool's distinct output clear.

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 phrase 'high-value targets for getting mentions' implies the use case (link-building / mention acquisition), but there is no explicit when-to-use vs when-not guidance and no named alternative such as list_missed_citations or list_competitors, leaving the agent to infer the routing.

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