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

Annotations already set readOnlyHint=true, and the description adds 'Free discovery' and explains what information is returned. It does not contradict annotations. It provides useful behavioral context (time shape, coverage limits, paste-ready query) beyond the annotation, enriching the agent's understanding of the tool's output and role.

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?

Two tight sentences with information front-loaded: first states return value, second gives usage guidance. No filler words, and every clause adds value.

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 single-parameter, read-only tool with no output schema, the description covers what the tool returns, when to use it, and why it matters. It includes specifics like 'time shape, coverage limits, and the paste-ready first query' which gives an agent everything needed to invoke it appropriately.

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% with pack_id described as 'Pack identifier from get_catalog'. The description adds no additional parameter details beyond the schema, so the baseline 3 applies.

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 ('Returns') and resource ('detailed metadata, coverage, freshness, preferred canonical tool guidance, and first-query examples for one pack'). It clearly distinguishes from get_catalog by focusing on a single pack and positioning it as a discovery step before querying, making its purpose unambiguous.

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?

Explicitly says 'Call this before querying a new pack', which gives a concrete use condition. It also hints at when it is not needed (when you already know the pack details). It does not name alternative tools explicitly, but the context makes it clear this is a pre-query discovery step.

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