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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does not mention accepted date formats, return values, validation semantics, failure behavior, or any side effects. The empty input schema makes the behavior even more opaque.

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 short, but this is under-specification rather than disciplined conciseness. The phrase 'Is Date Valid' is simply repeated with no added meaning, so the sole sentence does not earn its place.

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?

Even with an empty schema, a validation tool needs to explain what date is being validated, what counts as valid, and what output the caller can expect. With no output schema and no annotations, the description leaves the tool effectively unusable and inexplicable.

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 tool has zero parameters, so there are no parameter semantics that the description needs to clarify; a zero-parameter tool receives the baseline score of 4. The description adds nothing about parameters, but nothing is required in this case.

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 is 'Is Date Valid: Is Date Valid', which merely restates the tool name and provides no actual statement of what the tool does, what inputs it accepts, or what results it produces. It is a pure tautology with zero informative content.

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?

There is no guidance about when to use this tool, what conditions call for it, or which sibling tools should be preferred. An agent cannot determine whether to select this over the many other date-related or validation tools in the sibling list.

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