weather

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

With no annotations provided, the description carries the full burden and does well: it discloses the data source (MET Norway), the per-call cost ($0.002 USDC), and p99 latency (1500ms). It omits error/failure behavior and rate limits, so it is not exhaustive, but the operational context is far above baseline.

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?

Front-loaded with the core purpose, then a well-organized breakdown of current vs daily fields, params, and cost/latency. It is dense rather than rambling, though the return-field inventory is longer than strictly necessary.

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, so the description correctly enumerates the returnable current and daily fields, plus cost, latency, and param defaults. An agent has everything needed to call it correctly aside from the days-range error noted above.

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?

It enumerates all four params with defaults and even explains enum values, adding real value over the 75% schema coverage. However, it states days '1 to 16' while the schema caps maximum at 10 and its own schema note says the model reaches ~9.5 days — an inaccurate range that could lead an agent to request an invalid value.

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 resource (weather forecast + current weather) with an explicit scope ('any city or lat,lon worldwide') and names the upstream source (MET Norway). No sibling tool overlaps with weather, so an agent can identify it immediately.

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?

Gives clear context for use: worldwide coverage, forecast horizon, and the accepted location formats. It notes 'forecast_3d is kept for older clients,' which is a useful routing hint, but it never states when NOT to use this tool or how it relates to geocode for resolving ambiguous place names.

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