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

Annotations already cover read-only and open-world behavior, and the description adds two things they don't: the call consumes Weatherbit quota, and the usable horizon is plan-dependent. It doesn't mention rate limits or what happens when days exceeds the plan horizon (error vs truncation), which keeps it from a 5.

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 short sentences, zero filler, with the capability stated first and the cost/plan caveat second. Every clause carries information an agent needs.

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?

With no output schema, the description usefully lists the returned field categories, and it flags the quota cost and plan-dependent horizon. The main residual gap is behavior at the horizon boundary and the default value of days.

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 coverage is 75%; lat, lon, and units are documented in the schema, while 'days' has no schema description. The phrase 'up to 16 daily forecasts' does convey the practical ceiling for days, but nothing is said about default day count or how days interacts with plan horizon.

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 ('Get up to 16 daily forecasts') and enumerates the returned fields (temperature, precipitation, wind, conditions). The word 'daily' implicitly separates it from hourly/minutely/current siblings, but no sibling is 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?

There is no guidance on when to choose daily over weatherbit_hourly_forecast, weatherbit_current_weather, or the agriculture/energy variants, and no exclusions or prerequisites. The only contextual note is a quota/plan caveat, which is about cost, not selection.

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