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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, but the description adds rich context: it only includes explicit operational-disruption terms, retains all articles in the collection window, returns an unchanged API array, and never invents alerts. It also discloses payment requirements and the 402 return behavior, going well beyond structured 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 front-loaded with the core purpose and then provides compact coverage of scope, alternatives, payment, and return shape. The 'current publisher denominator' phrasing is slightly jargon-heavy, but every sentence adds useful information with minimal 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?

Given no output schema, the description compensates by explicitly stating the returned array shape: '{ headline, summary, source, port_code, severity, published_at }.' It also covers source scope, filtering behavior, payment/error handling, and sibling alternatives, making the tool fully usable without further research.

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%, so the input schema already documents every parameter. The description adds no additional parameter-level meaning beyond what the schema provides, making baseline 3 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+resource: 'Get certified shipping-disruption publications from reviewed official port-authority sources.' This clearly distinguishes it from sibling tools like shippingrates_congestion and shippingrates_risk_score, and the title 'Shipping Disruption News' reinforces the purpose.

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 alternatives are provided: 'For quantitative measurements, use shippingrates_congestion. For route-level risk scoring, use shippingrates_risk_score.' This tells the agent when not to use this tool and where to redirect, which is exactly the desired guidance.

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