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

Annotations already declare readOnlyHint and openWorldHint, but the description adds value by explicitly stating the open-world behavior ('Not every park has a curated list; an empty result is not an error') and clarifying the curated vs. raw distinction. It does not contradict annotations and provides useful context beyond the structured fields.

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 dense but every sentence earns its place. It front-loads the core purpose and content, then clarifies the distinction, input constraints, and edge-case behavior. No redundancy or 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?

Given the tool has 5 params and an output schema, the description covers the key aspects: purpose, input requirements, empty-result behavior, and differentiation from a sibling. It does not clarify what happens if both parkCode and stateCode are provided (though schema implies 'or'), nor does it describe the output format in detail, but the output schema covers that. Overall, it's quite complete for an agent to use 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?

Schema description coverage is 100%, so baseline is 3. The description adds extra meaning: it emphasizes that parkCode is a single code (not a list), specifies that at least one of parkCode/stateCode is required, and cross-references nps_find_parks for obtaining park codes. These details go beyond the schema's descriptions, justifying a 4.

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+resource (returns curated activities) with a concrete use case ('what should I do at Acadia?') and lists the content fields. It explicitly differentiates from the sibling nps_get_park by noting the curated list vs. raw activity tags, making it easy for an agent to select the right tool.

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?

It names the alternative (nps_get_park) and the condition that selects it (raw tags vs. curated list), and explicitly states the input requirement ('at least one is required' for parkCode/stateCode). It also sets expectations for empty results ('an empty result is not an error'), giving clear when-to-use and when-not-to-use guidance.

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