get_hourly_forecast

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

Annotations already indicate read-only, idempotent, non-destructive behavior. The description adds meaningful operational context: return units, default behavior, error result on out-of-range coordinates or API unavailability, and regional coverage. No contradiction with annotations.

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?

Four sentences, front-loaded with the core purpose, then usage guidance, units, error behavior, and coverage. Every sentence provides distinct value and there is no fluff or redundancy.

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?

Despite no output schema, the description clearly explains return content, units, default range, error behavior, and geographic coverage. This is sufficient for an agent to select and invoke the tool correctly and interpret results appropriately.

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?

Input schema already fully documents all three parameters with ranges and defaults (100% coverage). The description reinforces the hours default and coordinate range constraints but does not add significant new parameter-level semantics beyond what the schema provides.

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 ('hour-by-hour weather forecast'), with clear scope (1-48 hours, default 24) and content (temperature, wind, precipitation, conditions). Explicitly distinguishes itself from siblings by naming get_current_weather, get_daily_summary, and get_forecast.

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 a concrete use case ('will it rain in the next few hours') and explicitly lists when to use alternative tools (get_current_weather for a single now-reading, get_daily_summary for multi-day overview, get_forecast for complete raw dataset). Also provides coverage and error conditions.

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