mercury_retrogrades

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

With no annotations provided, the description carries the full burden of disclosure. It does a good job by explaining default date ranges ('now through +90 days'), the paired nature of the results, and the need to start the range before today for current retrograde checks. It does not describe exact output structure, but the output schema covers that.

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 well-structured: purpose first, then usage guidance, then argument details. Every sentence provides useful information, and there is no repetition or fluff.

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 tool with two optional parameters, clear defaults, and an output schema, the description is complete. It covers invocation scenarios, parameter semantics, and behavioral nuances, so the agent can select and call it correctly without additional context.

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 schema only provides parameter names and types, with zero description coverage. The tool description compensates fully by explaining each parameter's meaning, format, and default behavior, including examples and guidance on omission.

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 'List Mercury retrograde windows (paired start/end dates) within a date range,' which names a specific action, resource, and scope. It distinguishes itself from sibling tools by focusing on Mercury retrograde periods rather than moon-related phenomena.

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 lists example user queries that should trigger this tool and explains how to handle the 'right now' case. It does not explicitly state when not to use it or name alternative tools, but the use cases are clear and cover the main scenarios.

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