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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so safety and determinism are covered. The description adds genuinely useful context the annotations lack: the group membership (Cosmobiology / Hamburg School) and the cost of 10 credits (Tier 1), which matters for a paid call. It still says nothing about what the render actually returns or its computation traits.

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 very short and front-loaded, and the bracketed group/cost lines do earn their place by conveying billing and taxonomy. However the substance is so thin that the brevity reads as under-specification rather than tight writing.

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 16-parameter tool with 31% schema coverage, the description is far too sparse. It omits any explanation of the resource itself, offers no sibling routing, and leaves most parameters undocumented; only the presence of an output schema spares it a lower score on return values.

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 31% across 16 parameters, so the description is expected to compensate and does not. Undocumented or thinly-documented parameters such as fields, precision, cosmogram, zodiacType, houseSystem and withTnp receive no explanation in the description text.

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 'Ebertin cosmogram render data' essentially restates the tool name and title (Cosmogram / 90° Render Data) without explaining what a cosmogram is or what output it produces. It offers no differentiation from close siblings like astroway_cosmobiology_dial_90, midpoint_pictures, or witte_formulas, all of which operate in the same 90° Hamburg School space.

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, or alternative-routing guidance anywhere in the description. An agent has no basis for choosing this over the many other cosmobiology render tools beyond the bare name.

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