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

Annotations already declare read-only, idempotent, non-destructive, and closed-world behavior. The description adds useful operational context: the astrological criteria used (universal Pushya/Hasta and shubha tithis), that it returns top-N days, the endpoint, and the 50-credit cost.

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 text is front-loaded with the tool's purpose and criteria, followed by compact bracketed metadata. It is efficient and well-structured, though the endpoint/cost block is slightly extraneous to pure tool selection.

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 10-parameter tool with only 40% schema description coverage, the description is incomplete. It does not explain how to constrain the search window or set location, timezone, ayanamsa, or topN, all of which are important for a muhurat finder. The output schema covers return values, but parameter guidance is largely missing.

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?

Schema description coverage is only 40% across 10 parameters, so the description should compensate but does not. It mentions the required search_window_start only, leaving topN, ayanamsa, latitude, longitude, timezoneOffset, precision, fields, search_window_end, and ayanamsaId without added meaning in the description.

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 states a specific verb+resource ('favourable-window finder') and explicitly scopes it as the generic fallback when no specific activity applies. It names the criteria used (Pushya/Hasta nakshatras, shubha tithis) and distinguishes itself from the many activity-specific muhurat siblings.

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?

It clearly says to use this when no specific activity applies, with Sankalpa, prayer, and fallback as examples. It implies the activity-specific muhurat tools should be used instead but does not name any alternative tool, so it falls short of the top score.

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