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

The description discloses several behavioral traits not covered by annotations: it is a paid tool ($0.02/call via x402), returns 402 without payment, passes through the API array unchanged, retains all articles in a finite collection window, filters by explicit operational-disruption terms, and never invents alerts. This adds significant context beyond the readOnly, idempotent, non-destructive hints.

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 efficiently structured: a one-sentence purpose statement, a paragraph of behavioral details, sibling differentiation, payment info, and return format. Every sentence carries value and is front-loaded with the most important information.

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?

Despite having no output schema, the description specifies the return array fields. It covers payment requirements, fallback behavior (402), source limitations, filtering logic, and sibling alternatives. For a read-only news retrieval tool with well-documented parameters, this is a thoroughly complete description.

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 input schema has 100% description coverage, so the schema already documents all parameters (port, limit, severity, days_back, x_payment). The description does not add significant parameter-level meaning beyond mentioning the return array fields and the concept of a finite collection window. Baseline 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 opens with a specific verb and resource: 'Get certified shipping-disruption publications from reviewed official port-authority sources.' It further clarifies the exact publisher sources (Port of Rotterdam and Port of Los Angeles) and distinguishes itself from sibling tools by naming shippingrates_congestion and shippingrates_risk_score as alternatives for different needs.

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?

Explicit when-to-use guidance is provided: 'For quantitative measurements, use shippingrates_congestion. For route-level risk scoring, use shippingrates_risk_score.' It also explains behavioral nuances, such as returning empty results rather than fabricating alerts, which informs appropriate use.

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