historical_weather

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

With no annotations and no output schema, the description carries the full burden, and it does disclose two useful behavioral facts: the data source (Open-Meteo archive) and the hard temporal limit (1940 to 5 days ago). However, it says nothing about granularity guarantees, units, rate limits, or what a request for an out-of-range date returns.

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 front-loaded sentence naming the verb, resource, source and range with zero filler. Every clause earns its place.

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 source-less, annotation-less, output-schema-less data-fetch tool, the description covers provenance and date bounds but omits the returned variables/daily aggregation and error behavior for out-of-range dates. Adequate but not fully self-contained.

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 4 required params, so the schema already documents latitude, longitude, start_date and end_date formats. The description adds only the valid date window, which slightly informs the date params but is not parameter-specific syntax or constraints. Baseline 3.

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 ('Get') and resource ('historical daily weather data') plus the upstream source (Open-Meteo archive) and temporal scope, which distinguishes it from siblings like weather_forecast, weather_hourly and weather_current. It stops short of explicitly naming those alternatives, so it earns a 4 rather than a 5.

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?

The '(1940 to 5 days ago)' bound implies when this tool is appropriate (past dates, not forecasting), but there is no explicit when-to-use statement and no mention of the obvious alternatives such as weather_forecast or climate_normals. Usage is inferred rather than stated.

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