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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds no additional behavioral context such as pagination, response format, rate limits, or data freshness, so it fails to contribute transparency beyond the annotations.

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?

The description is a single, front-loaded sentence that efficiently conveys the core action and operation with zero extraneous words.

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 2-parameter read-only tool, the description adequately defines its function. The lack of an output schema is mitigated by the tool's clear purpose, though an explicit statement of the return value (e.g., 'returns a list of domains') would improve completeness.

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 no schema descriptions, the description compensates by mapping domain_a to A and domain_b to B, clarifying the asymmetric relationship (links to A but not B). This adds meaning beyond the bare string type definitions, though it does not specify domain formatting details.

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 clearly states a specific verb ('Find') and resource ('domains linking to A but not B'), which precisely differentiates it from sibling tools like get_domain_overlap that would find domains linking to both. It unambiguously defines the set-difference operation.

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 makes the intended use case obvious: identify domains exclusively linking to A but not B. While it does not explicitly mention alternatives or exclusion criteria, the context is clear enough that an agent can infer when to use it versus a similar overlap tool.

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