Hyleg Longevity

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely useful operational context that annotations do not: a cost of 10 credits (Tier 1) and the POST endpoint. It does not explain what the calculation actually produces or any limits, so it is a modest add rather than rich behavioral detail.

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?

It is short and front-loads the technique reference, but four of the five lines are bracketed metadata tags (group, endpoint, required, cost) rather than substantive content. There is little waste, but also little value per line.

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 13-parameter computation with 23% schema coverage, the description is far too thin: it does not explain the method, the output, or the meaning of ten undocumented parameters. The existence of an output schema excuses explaining return values, but the input side remains inadequately covered.

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 23% across 13 parameters, so the description needs to carry the load, and it does not. It merely restates the four required parameters already declared in the schema ('Required: date, time, latitude, longitude') and never mentions city, name, cosmogram, houseSystem, zodiacType or the ayanamsa options.

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 citation 'Tetrabiblos III.10 hyleg + alcocoden' identifies the astrological technique (longevity hyleg/alcocoden) but uses no verb and no plain-language statement of what the tool returns. It is not differentiated from the sibling astroway_dignities_hyleg, which also deals with the hyleg, so an agent cannot tell them apart from the description alone.

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 guidance about when to use this versus alternatives such as astroway_dignities_hyleg or other Hellenistic Hand tools. The only context provided is a group tag and endpoint, which do not convey usage conditions.

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