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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: a 7-day window and Malay-language summaries (relevant for downstream parsing), but omits auth requirements, rate limits, and what happens when no location matches.

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?

A single well-formed sentence that front-loads the provider and forecast horizon, then the returned fields. Every clause earns its place with no redundancy.

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?

Because an output schema exists, return-value structure need not be explained. The description covers the essential call context (provider, horizon, granularity, language of output) and annotations cover safety, so only edge-case behavior and usage routing are thin.

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 100% with all four parameters (limit, date_start, date_end, location_name) documented in the schema. The description only restates 'by location' and adds no format or matching-semantics detail beyond what the schema already provides, so the baseline of 3 applies.

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 specific verb (Get) and resource (Malaysian Meteorological Department 7-day forecast) and states the content returned: morning/afternoon/night conditions plus min/max temperature. It is clearly distinguishable from the sibling malaysiagov.weather.get_warnings, though that sibling is not named explicitly.

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?

Usage is implied by the resource name — an agent can infer this is for forecast retrieval rather than warnings or earthquake data — but there is no explicit when-to-use statement, no mention of the warnings/hazards siblings, and no guidance on whether dates or location are preferred filters.

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