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

Annotations already declare readOnly=true, idempotent=true, non-destructive, closed-world, so the safety profile is fully covered. The description adds only the cost tier and endpoint, useful operational context but no behavioral detail beyond annotations. A 3 reflects that the description neither adds much nor contradicts.

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?

Four lines, each earning its place: the one-line purpose plus bracketed metadata for group, endpoint, required params, and cost. Efficient and front-loaded, though the bracketed lines are somewhat machine-oriented rather than explanatory.

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 15-parameter astrological calculation tool with only 33% schema coverage and many domain-specific options (ayanamsa schools, house systems, zodiac types), the description is far too thin. It doesn't explain what the output contains, what 'trine to rising sign' means in context, or how the optional params affect results, even though an output schema exists.

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 33%, so many parameters (city, name, cosmogram, zodiacType, houseSystem, ayanamsaId) are undocumented. The description lists required params (date, time, latitude, longitude) which matches the schema's required array, but adds no syntax or semantic meaning beyond that, and doesn't compensate for the coverage gap.

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 'Bodies trining the rising sign' states the astrological phenomenon being computed, which is more specific than restating the name 'Horoskopos Trine'. However, it doesn't fully explain what the tool returns (a list of bodies? an analysis?) and doesn't differentiate from sibling Hellenistic tools like hand_perfections or hand_bounds.

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?

No when-to-use guidance, no alternatives named, no prerequisites. The endpoint metadata implies it takes a birth chart, but nothing tells an agent when this Hellenistic technique is appropriate versus the dozens of sibling Hellenistic tools.

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