date_difference_calculator

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the tool calculates days/weeks/months but does not disclose the output format (e.g., whether it returns a single number, multiple values, or an object), nor any edge cases or behavior on invalid dates. This is a significant gap for a calculator tool.

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—a single sentence that front-loads the core purpose. There is no wasted text, and the input format hint is included. However, the brevity contributes to the lack of completeness, so it's not a 5.

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?

The description is incomplete for a tool with no output schema, no annotations, and 0% parameter coverage. It fails to specify the return value, which is critical for an agent to interpret results. It also doesn't mention whether it returns all units (days, weeks, months) or a choice, or any behavior for edge cases. The description is too sparse to fully guide correct invocation.

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 description adds the date format YYYY-MM-DD, which is useful given the schema has no descriptions. However, it doesn't explain the meaning of startDate and endDate beyond the obvious, nor does it clarify ordering or validation. Since schema coverage is 0%, this is partial compensation but insufficient for full clarity.

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 the tool computes the difference between two dates in days, weeks, or months. It is specific about the resource (dates) and the operation (difference calculation), and it is distinguishable from sibling tools like age_calculator, though it doesn't explicitly call out alternatives.

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 the usage scenario (computing date differences) but provides no explicit guidance on when to choose this tool over alternatives or any exclusions. For example, it doesn't clarify when to use this versus age_calculator, though the purpose makes it somewhat obvious. Lacks explicit routing or 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.