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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered elsewhere. The description adds no behavioral context at all – nothing about what 'details' includes, error behaviour for unknown ids, or rate limits – so it earns little credit beyond not contradicting 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?

A single well-formed sentence that front-loads the purpose and embeds the id source and examples. Nothing is wasted.

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 one-parameter read-only lookup with rich annotations, this is close to sufficient. The only gap is that, with no output schema, the description never hints at what fields the package details contain.

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 coverage is 100% and the single parameter is already described as 'Package id from list_packages'. The description adds genuine value beyond the schema by giving concrete id-format examples ('tr-10gb-30d', 'tr-daily-3gb'), which helps the agent construct or validate the argument.

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?

States a specific verb/resource pairing ('Details of one package') and even names the sibling that produces the required id ('the id that list_packages returned'). It stops short of an explicit 'use X instead' routing statement, but an agent can distinguish it from list_packages without opening the schema.

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 precondition is clear: this tool is for when you already have an id obtained from list_packages. There is no statement of when-not to use it or a named alternative for other lookups, which keeps it at 4 rather than 5.

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