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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, closed world), so the bar is lower. The description usefully adds cost information ('10 credits (Tier 1)') and the group tag, which annotations do not carry, but says nothing about the calculation's behavior, required inputs, or failure modes.

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?

Two content sentences plus bracketed metadata, front-loaded with the verb and resource. The bracket lines are boilerplate but short; nothing is padded.

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?

An output schema exists, so return values need no explanation, but the description leaves the three required, undescribed inputs ambiguous — notably the pronunciation-sensitive name input that defines this system — and offers no guidance for choosing between the many personal_year siblings.

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%: the three required parameters (name, date, year) carry no schema descriptions, and the description does not compensate. For a phonetic Kabbalistic system it never explains that 'name' must be the full birth name as pronounced, nor clarifies the date/year interaction, leaving the most consequential inputs undocumented.

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 and resource ('Calculate the Personal Year number for a given calendar year') and pins the system variant as 'Kabbalistic (phonetic)', which is the key discriminator among the many personal_year siblings (chaldean, pythagorean, vedic, strict, numk/numks/nump). It does not, however, explain how it differs from the adjacent 'kabbalistic_strict_personal_year' or the abbreviated numk/numks variants.

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 explicit when-to-use or when-not-to-use statement and no sibling is named as an alternative. The system label implicitly narrows the choice, but with roughly ten personal_year tools in the list an agent gets no routing help beyond the system name.

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