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

Beyond the readOnlyHint annotation, the description discloses the exact return fields (name, type, website, parent, children, domain status, metadata) and highlights flexibility in hierarchy depth. This adds valuable context about what the agent can expect. It does not contradict annotations and covers the read-only nature adequately.

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 two sentences with no filler. The primary action and resource are front-loaded, followed by concrete examples and scope clarification, then a concise list of return fields. Every sentence earns its place, making it easy for an agent to parse quickly.

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, single-parameter read-only tool, the description covers all necessary guidance: what it does, how to specify the target (slug), what it returns, and its applicability at any hierarchy depth. Without an output schema, the explicit field list is sufficient. No missing information prevents correct invocation.

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 already provides a thorough description of the slug parameter with examples, and schema coverage is 100%. The description adds examples and mentions broad hierarchy support, which reinforces but doesn't materially extend the schema's meaning. This meets the baseline for high schema coverage.

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 states a specific verb ('Get') and resource ('full details for a specific government entity') with a precise identifier (URL slug). It clearly distinguishes from sibling tools like search_entities, which perform searches, and list_countries, which list all entities. The hierarchy depth clarification (cities, school districts, special districts) further nests the tool's unique scope.

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 provides clear context for when to use the tool: when you have a specific slug at any hierarchy depth. It gives multiple examples but does not explicitly mention alternatives or exclusions. However, the implied use case (retrieve by known slug) is unambiguous, and the sibling names (e.g., search_entities) make the distinction obvious without needing explicit 'don't use when searching' guidance.

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