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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds useful operational context — the POST endpoint, that 'year' is required, and a cost of 100 credits (Tier 4) — but discloses no additional behavioral traits beyond that.

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?

Two front-loaded sentences state purpose and return contents, followed by a compact bracketed metadata block for group, endpoint, required param, and cost. Little waste, though the return-content sentence is partly redundant given an output schema exists.

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 simple lookup tool, the description covers endpoint, required parameter, cost tier, and output fields, with annotations carrying the safety profile and an output schema handling return structure. The main gap is the unexplained interaction between the 'year' and 'yearsRange' parameters.

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 50%: the schema documents 'fields' and 'precision', but 'year' and 'yearsRange' are bare. The description's phrase 'year or multi-year range' hints at the year/yearsRange distinction but does not explain when one supersedes the other, so it only partially compensates 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?

States a specific verb and resource ('Find solar and lunar eclipses') plus scope ('within a given year or multi-year range'), and the response contents ('type, date, and geographic visibility data'). It is clear what the tool does, though it does not differentiate itself from the nearby sibling astroway_geo_eclipse_analysis.

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 description mentions that eclipses can be found in 'a given year or multi-year range' but never states when to use this tool versus alternatives such as astroway_geo_eclipse_analysis or astroway_render_eclipse_path, and gives no exclusions or prerequisites. Usage must be entirely inferred.

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