get_forecast

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

With no annotations, the description carries the full burden, and it does disclose one important behavioral limit: the 16-day forecast horizon. It says nothing about units, timezone, or what happens when a date is out of range, so the disclosure is partial.

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 one-line summary followed by a tight two-item Args block; every line carries information. Slightly repetitive docstring formatting, but no wasted content.

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?

For a two-parameter read tool with an output schema already defining return values, the description covers the essentials: what is returned, the date format, and the valid date window. Only minor gaps remain (units, timezone, out-of-range behavior).

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 0%, but the description compensates well for both parameters: 'city' gets a concrete example (Lisbon) and 'day' gets a format ('YYYY-MM-DD') plus a range constraint ('within the next 16 days') that the schema does not express at all.

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 first sentence gives a specific verb ('Get') and resource ('weather forecast') with an explicit scope ('for a city on one day'). It is unambiguous what the tool returns, though with no sibling tools there is no differentiation work to do.

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 rather than stated: the agent learns the day must fall 'within the next 16 days,' which is a real applicability constraint. There is no guidance on when not to use it or what to do for dates outside that window.

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