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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the description adds the credit cost (10 credits, Tier 1) and the endpoint group, which is genuinely useful quota information not present in structured fields. It says nothing about response shape, caching, or limits, but the output schema covers return values.

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?

Very compact and front-loaded: the purpose sentence comes first, followed by scannable bracketed metadata for group, endpoint, required inputs, and cost. The POST endpoint URL is arguably dead weight for an MCP caller, but nothing else 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?

With an output schema present, return values need not be described, and annotations carry the safety profile. What remains missing is any explanation of the eleven optional parameters this tool exposes, which for a 15-param astrological calculation is a meaningful gap even if the shared parameter block is documented elsewhere.

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 33% (15 params), and the description contributes nothing beyond restating the four required fields already declared in the schema's `required` array. Cryptic params such as the 25 single-letter `houseSystem` enum, `cosmogram`, `zodiacType`, and `ayanamsaId` are left unexplained in both schema and description, so the description fails to 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?

"Aspect classes per Schmidt" names a topical domain but no verb or output, so the agent cannot tell what is actually computed or returned. It does distinguish the tool topically from the many other Schmidt modules (sect_classes, lord_of_prediction, etc.) and discloses that it duplicates the canonical `astroway_hellenistic_schmidt_aspectual_typology`, which aids identification, but the purpose itself remains vague.

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 statement of when to choose this tool over the other Schmidt analysis modules or when its output is relevant. The only selection-relevant signal is the parenthetical alias note, which implies the agent should not call both this and the canonical name; that is identity information, not usage guidance.

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