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

Annotations already declare readOnly, idempotent, closed-world and non-destructive behavior, so the safety profile is covered. The description usefully adds the endpoint, the 10-credit Tier 1 cost, and the required-field set, but says nothing about the response contents or precision/compact-mode behavior beyond what the schema carries.

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?

The definition is compact and front-loads the one substantive phrase before the bracketed metadata. Each line carries information, though the result is so terse that brevity shades into under-specification.

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 tool with only 33% schema coverage, this is thin: the compact `fields`/`precision` options, sidereal vs tropical handling, and house system selection go unexplained. The output schema exists so return values need not be described, but the invocation surface is not covered.

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%, so the description must compensate for a large set of undocumented parameters (city, name, cosmogram, zodiacType, houseSystem, ayanamsaId). It only restates the four required fields already marked in the schema's required array, adding no meaning for the eleven others or for the ayanamsa/ayanamsaId duality.

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 phrase "8 Hamburg trans-Neptunian bodies" names a specific resource, so the agent knows this is the Hamburg School TNP set rather than one of the sibling tools' outputs. But there is no verb (compute? list? ephemeris?) and nothing that distinguishes it from neighbours like astroway_cosmobiology_witte_formulas or lefeldt_extensions, leaving the purpose only implied.

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?

The only usage signals are the "[Required: date, time, latitude, longitude]" and cost lines, which are constraints rather than guidance. It never says when to choose this over the other cosmobiology endpoints or what input conditions it expects.

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