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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description still adds materially: the credit cost (10 credits, Tier 1) is an invocation-time consideration agents may need to weigh, plus the endpoint and grouping. It does not describe error or validation behavior, but that gap is modest.

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 core sentence is front-loaded and tells the agent what the tool returns before the bracketed metadata. The group/endpoint/required/cost lines are compact and scannable, though the endpoint line duplicates the group line's information for an agent that cannot make HTTP calls.

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-value documentation is unnecessary, and the annotations cover the safety profile. With the system variant named, cost disclosed, alias noted, and required inputs identified, an agent has everything needed to choose and call this tool correctly.

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 at 50%: `fields` and `precision` are well documented in the schema, but `name` and `date` carry only constraints (pattern, min/maxLength) with no prose. The description's '[Required: name, date]' merely restates the schema's required array and adds no semantic detail, so it does not compensate for the undocumented half.

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 ('Calculate') and resource ('four Pinnacle cycles with their age boundaries') and pins the exact system variant ('Kabbalistic (Mathers strict)'), which is what separates it from the pythagorean/chaldean/vedic pinnacle siblings and from the other kabbalistic-strict aspect tools. It also discloses the alias relationship to `astroway_numerology_kabbalistic_strict_pinnacles`, so an agent can recognize the duplicate.

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 alias note is genuinely useful for tool selection, telling the agent this and the long-named variant are interchangeable. However, there is no explicit when-to-use / when-not guidance relative to the other numerology aspect tools (life_path, challenge, maturity), leaving the agent to infer that 'pinnacles' means the age-chapter reading.

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