floor

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

With no annotations, the description carries the burden of behavior disclosure. It explains string input support, the lack of formatting handling, and the unchanged integer case. This is solid behavioral context, though it omits edge cases like non-numeric strings.

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?

Three concise sentences, front-loaded with the primary purpose. Every sentence earns its place: the core operation, input constraints, and an edge case.

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 math function, the description covers the operation, input constraints, and integer edge case. It lacks an explicit output type statement, but the return behavior is implied well enough.

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 no properties, so the description adds essential semantics by explaining that numbers can be passed as strings. It also clarifies that formatting like commas is not supported, which is valuable beyond 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?

The description clearly states 'Rounds a number down to the nearest integer,' which is a specific verb and resource. It distinguishes itself from siblings like ceil and round by specifying the downward direction.

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 provides clear context: use this when you need to floor a number. It also gives limitations (no commas or formatting in numeric strings), but does not explicitly name alternatives or situations where ceil/round would be preferred.

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