is_finite

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

No annotations are provided, so the description carries the full burden. It clearly states the tool's behavior (checking if a number is finite), but doesn't disclose additional traits like error handling, performance characteristics, or what happens with non-numeric inputs. The description is accurate but lacks depth for a tool with no annotation support.

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 extremely concise (one sentence plus domain/category) with zero wasted words. It's front-loaded with the core functionality and uses parentheses efficiently for additional context. Every element earns its place in this minimal but complete description.

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 comparison tool with one parameter and no output schema, the description provides sufficient context about what the tool does and what it expects. The domain/category annotation adds helpful context. However, without annotations or output schema, it could benefit from mentioning the return type (likely boolean) or edge case behavior.

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?

With 0% schema description coverage and only one parameter ('x'), the description adds meaningful context by specifying that the input should be 'a number'. This compensates well for the lack of schema documentation, though it doesn't provide format details or examples. The baseline would be lower with more parameters, but for a single parameter tool this is adequate.

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 explicitly states the tool's purpose with a specific verb ('Check') and resource ('a number'), clearly distinguishing it from siblings like 'is_infinite' and 'is_nan' by specifying 'finite (not infinite and not NaN)'. It also includes domain/category context that helps differentiate it from other comparison tools.

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 implies usage context through the domain/category annotation ('arithmetic, comparison'), which helps situate it among mathematical tools. However, it doesn't explicitly state when to use this tool versus alternatives like 'is_infinite' or 'is_nan', nor does it provide exclusion criteria or prerequisites for usage.

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