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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds real behavioral value beyond that by disclosing the exclusion rules (Kharmas, Adhik Maas, Chaturmas) that determine which dates appear, though it says nothing about output volume or ordering.

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 tight sentences: what it returns, what it filters out, and who it is not for. Zero filler and the output content is front-loaded.

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 single-parameter, no-output-schema tool with full annotations, the description covers return contents, filter rules, and personalization scope. The only gap is the year range, which is left to the schema.

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 0%, so the description must carry the load; it only implies a year input via 'for a year'. It does not mention the 2024–2035 valid range that the schema enforces, so an agent relying on the prose alone could pass an out-of-range year.

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?

States a specific verb+resource ('shubh marriage dates for a year') and enumerates the returned fields (muhurat time, nakshatra, tithi, lagna). The 'strict-classical' qualifier plus the marriage scope cleanly separates it from siblings like shubh_muhurat and muhurat_karma_list.

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?

Gives clear scope conditions: it excludes Kharmas, Adhik Maas and Chaturmas, and is explicitly 'not personalised to any birth chart', which implicitly routes personalized queries elsewhere. It stops short of naming which sibling to use for chart-specific muhurat, so no explicit alternative is provided.

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