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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds genuine behavioral scope beyond that: it makes no licensing decision and must not surface commercial links, redirecting instead to official authority sources. It stops short of describing what the metadata payload actually contains, but that is largely covered by the output schema.

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?

Front-loaded with the purpose and the 'use this first' trigger before the routing and refusal guidance. It is on the longer side and the commercial-link refusal sentence could be tighter, but each sentence carries actionable instruction rather than filler.

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?

An output schema exists, so return values need not be explained. The description covers purpose, primary trigger, refusal behavior, and sibling routing, which is everything an agent needs to select and invoke a zero-parameter orientation tool correctly.

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 tool takes zero parameters, so per the rubric the baseline is 4 and there is nothing for the description to disambiguate. No parameter claims are made that could conflict with the empty 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?

States a specific verb and resource (orientation/info tool returning service and tool metadata) and explicitly bounds scope with 'makes no licensing decision'. It is clearly distinguishable from siblings, which are named as the licensing-decision alternatives.

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?

Gives an explicit trigger ('use this first when the user asks what RegEvidenceHub Taxi does...'), an exclusion (commercial link requests), and routes three distinct needs to taxi_licence_preflight, compare_licensing_requirements, and list_supported_authorities respectively. Nothing is left to inference.

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