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

The description adds valuable behavioral context beyond the annotations: it discloses the credit cost (1 credit) and the condition 'no data = no charge', which likely means if no data is available for the domain, there is no charge. This is extra context that is not in the readOnly/idempotent hintsforth and helps the agent understand the transactional implications.

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 concise (two sentences), front-loaded with the core outcome (6-pillar readiness score), and includes key operational details (uniqueness, credit cost, no data/no charge). No waste.

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?

The description covers the purpose, output (tier and highlights), and operational constraint (credit). Given the tool has only one parameter and no output schema, the description is adequate. Minor gap: it does not specify what 'no data' means or how the credit is charged in detail, but the nuance 'no data = no charge' is captured.

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?

The schema defines 'domain' with 100% coverage, and the description mentions 'a domain' and 'domain to score' in the parameter description. The description adds a bit of context (readiness score) but does not provide deeper meaning beyond 'domain to score'. Since schema coverage is high, a baseline of 3 is appropriate.

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 the tool computes a '6-pillar AI/agent-readiness score' for a domain)Skip and highlights that it is uniquely RivalSweeper data. It is specific in what it measures (schema.org, technical access, content quality, trust, AI-specific, entity recognition) and notes the output includes tier and highlights. It does not explicitly distinguish itself from siblings, but the unique nature of the data implies differentiation.

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 indicates it can be used to score a domain's readiness and mentions a credit cost, but does not provide explicit when-to-use or when-not-to-use guidance or alternatives. The uniqueness of the data serves as a subtle implication that it is the only tool for this purpose, but that is not directly stated.

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