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

Annotations already provide readOnlyHint, destructiveHint, idempotentHint, openWorldHint, so the safety and idempotence are clear. The description adds no extra behavioral nuances beyond confirming it's a count operation and attributing data source (GBIF). With annotations, a score of 3 is appropriate.

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 concise sentences: first states the action and parameters, second states use cases and source. No redundant words, front-loaded with core purpose, every sentence 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?

Given the tool's simplicity (single count query with two parameters), the description covers purpose, parameters, use cases, and data source. The presence of an output schema (not shown) likely details return format, so the description is adequately complete for an agent to select and invoke.

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 has 100% description coverage for both parameters. The description adds only 'optionally filtered by country', which does not enhance the schema's existing description of the country parameter. Thus, no significant added value beyond schema, baseline 3.

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 total occurrence count for a species' with specific verb and resource. It mentions optional country filtering and lists concrete use cases (range size estimation, etc.), which distinguishes it from sibling tools like 'gbif.biodiversity.occurrences' that return actual records.

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 explicitly mentions three use cases (range size estimation, data density assessment, conservation status analysis) that signal when to use this tool. While it doesn't directly contrast with alternatives, the use cases imply it's for aggregate counts rather than detailed records.

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