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 structurally. The description adds only a cost note and nothing about auth, computation semantics, or what 'compatibility' means here, so it contributes almost no behavioral context beyond annotations.

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 a fragment, but the brevity comes from under-specification rather than precision. The bracket metadata lines occupy most of the content while the actual purpose goes unstated.

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 not be described, but for a 15-parameter astronomy/psychology tool with opaque enums and no sibling differentiation, this description is far too thin to let an agent invoke it correctly. It omits prerequisites, output shape hints, and any distinction from the many parallel relational/element tools.

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?

With 15 parameters, only ~33% schema description coverage, and cryptic enum values (houseSystem codes P/K/R/C/W..., ayanamsaId as an undocumented number|null), the description is the place to compensate but says nothing about any parameter. Required inputs date/time/latitude/longitude and the meaning of 'fields' compact mode are left entirely to the schema.

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 reduces to 'Relational element compatibility map,' which essentially restates the title 'Arroyo: Relational Map' without a verb or any statement of what is actually computed or returned. It does not distinguish this tool from its near-identical siblings, notably astroway_psya_relational_element_map and astroway_psychological_modern_arroyo_element_balance.

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 on when to use this tool, when not to, or which sibling to prefer. The only extra content is group/cost metadata ('10 credits (Tier 1)'), which is pricing, not usage context.

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