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

No annotations exist, so the description carries the full behavioral burden, and it discloses almost nothing beyond scope. It never says whether times are returned in the requested utc_offset or local time, what happens if place resolution fails, whether a name and coordinates conflict, or what defaults apply when no date is supplied.

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 sentences with zero filler; the data covered is front-loaded and the use cases follow. Nothing redundant or padded.

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 no explanation, and the description correctly identifies all returned quantities plus inputs. It still omits timezone semantics and what happens when neither place nor coordinates are given — notable for a five-parameter, all-optional tool.

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% across five parameters, so the description must compensate and largely does not. It hints that 'place' may be a name or coordinates (covering place/lat/lon loosely) and mentions date, but utc_offset — despite defaulting to +00:00 — is never mentioned, nor are accepted date formats.

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 names a concrete resource — sunrise, sunset, solar noon, day length, sun elevation, moonrise, moonset, moon phase and illumination — scoped to 'any place (name or coordinates) and date'. It is immediately clear what the tool returns; the only miss is not differentiating from loosely adjacent siblings like weather_forecast or time_zone_convert.

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?

'Use for photography, prayer and event planning, solar or outdoor work' gives use-case context but no when-not conditions, no alternatives, and no guidance on choosing place-name vs lat/lon. Usage is implied rather than directed.

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