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

Annotations already provide readOnlyHint and idempotentHint, so the safety profile is established. The description adds useful behavioral context beyond this: 'No authentication required' and 'Policies are empire-wide — every station in an empire's space uses the same snapshot.' This clarifies scope and authentication expectations.

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 supplementary details in parentheses. It is slightly dense but every clause carries relevant information (fields returned, valid values, auth, scope, alternative). No redundant 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 read-only query tool with no output schema, the description is complete: it lists the returned categories, gives valid values, explains the default behavior, notes authentication, clarifies scope, and points to an alternative. The schema and annotations cover the remaining structural aspects.

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%, so parameters are already documented with enums and descriptions. The description adds semantic value by giving an example payload and clarifying the default behavior when empire_id is omitted ('omit to get all five'), which is not explicitly in the schema.

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 'Get the live policy snapshot for one or all empires' with a specific verb and resource, and enumerates the exact contents (fees, tax rates, etc.). It also distinguishes itself from the sibling get_tax_estimate by directing users there for personalized projections.

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?

Provides explicit usage instructions: how to fetch a single empire ('Optional payload: {"empire_id": "solarian"}'), how to get all five (omit), valid empire_id values, and a clear alternative tool for personalized tax projections ('Use get_tax_estimate'). Also notes 'No authentication required,' which is a key prerequisite.

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