Planetary Cycles

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely non-structured context: the endpoint (POST /v1/planetary-cycles) and the pricing tier ('100 credits (Tier 4)'), which an agent needs for cost-aware planning. It stops short of noting any limits on range width or what happens when no conjunction occurs in the window.

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?

One load-bearing sentence followed by scannable bracketed metadata lines for group, endpoint, required params and cost. Front-loaded and free of filler, though the metadata block partly duplicates the required-params list already present in the schema.

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?

Annotations and an output schema are present, so return-value documentation is not owed. Still, for a compute-style endpoint with four undocumented parameters, the description would need to clarify the planet identifier scheme and any date-range constraints to be fully sufficient for a correct call.

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 0%, so the description carries the burden and only partly meets it: 'between two planets' maps to planet1Id/planet2Id and 'within a date range' maps to startDate/endDate. It adds no information about the planet ID numbering convention or that dates must be YYYY-MM-DD (that only comes from the schema pattern).

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?

Specific verb and resource: 'Find all conjunctions between two planets within a date range, defining the start of a new synodic cycle.' An agent immediately knows it returns conjunction dates that mark cycle starts. It does not, however, distinguish itself from nearby siblings such as astroway_calendar_planetary_phases, astroway_calendar_ingresses, or astroway_calendar_cyclic_index, so the differentiator must be inferred from the name.

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 when-to-use / when-not-to-use guidance and no named alternative. In a catalog with planetary_phases, ingresses, cyclic_index and rudhyar_cycles_of_becoming all plausibly adjacent, the agent is left to infer selection from names alone. The '[Group: Calendar & Cycles]' tag is a category label, not routing guidance.

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