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 context beyond structured fields: it discloses that results derive from real sunrise/sunset data, and that omitting date leaves the server on serverTime="SystemTime".

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, both front-loaded with the core transformation and then the return payload. No filler or restated title.

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?

No output schema exists, and the description compensates by naming the three return components (values, real durations, ready cfg block). Given the 5-param, enum-heavy schema, this is nearly complete; only per-parameter output detail and any edge cases (e.g. what happens if day+night exceed a cycle) are unaddressed.

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 80%, so map, date, lang, day_minutes and night_minutes are largely documented in the schema itself. The description adds the conceptual link between the minute inputs and the acceleration outputs, but no format or unit detail beyond what the schema already gives. Baseline 3 is appropriate.

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?

Names a specific transformation (wanted day/night real-time length → serverTimeAcceleration and serverNightTimeAcceleration for serverDZ.cfg) and states what it returns. No sibling tool overlaps this computation, so the agent can distinguish it cleanly.

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?

Explains the context in which the conversion applies (real sunrise/sunset of the map on the in-game date) and the schema notes what happens when date is omitted. It does not name an alternative tool or an explicit when-not-to-use condition, but for a single-purpose calculator there is little sibling ambiguity to resolve.

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