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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the description's added value is the quota cost, the paid-tier prerequisite, and the forecast horizon — exactly the operational context an agent needs. Return format beyond the named field groups is not covered, but the annotation floor makes that acceptable.

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, no filler. The capability statement leads and the constraint/cost caveat follows, which is the right ordering for an agent scanning for eligibility.

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 naming the included field groups (soil, evapotranspiration) partially compensates by signaling what comes back. Missing only a note on response shape or the fixed 8-day horizon length per entry, but the essentials for a correct call are present.

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 ranges and a units enum fully documented, so the schema carries parameter meaning entirely. The description adds no coordinate or units semantics of its own; baseline 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?

States a specific verb (read) and resource (8-day agriculture forecast) and names the distinguishing payload (soil and evapotranspiration fields). This clearly separates it from weatherbit_agriculture_history and the general daily/hourly forecast siblings.

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 concrete usage conditions — it consumes Weatherbit quota and requires agriculture API access (Business/Enterprise) — which tells an agent when it is even callable. It stops short of explicitly naming alternatives (e.g. use daily_forecast if agriculture access is unavailable).

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