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

Annotations already cover the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description adds scheduling context (built 'around the weather and what is open') and the five-slot output shape, which is useful, but it does not describe return structure, latency, or why openWorldHint=false despite referencing external weather/OSM data.

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?

Three sentences with the purpose front-loaded, but the random-city idea is repeated twice and the closing clause ('in a city, near a location, or in a random city') is redundant with the second sentence. Tightening would remove waste.

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 an 8-parameter, no-required-arg tool with no output schema, the description covers the core generation behavior but leaves the return shape only loosely implied and never explains what the response contains beyond segment names. An agent can call it, but a fuller account of the output (or seed/link behavior) is missing.

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%, so the schema already documents all 8 parameters and the baseline is 3. The description largely restates schema content ('leave out city...for a random city'), though it adds slight framing around the random/seed behavior, and it awkwardly refers to a 'location' parameter that is actually lat/lon.

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 (build/spin) and resource (a full day out) and enumerates the components produced (morning, lunch, afternoon, dinner, evening), so the agent knows exactly what it generates. It does not differentiate itself from the sibling list_vibes, which keeps it from 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?

Explicitly states the conditional behavior: 'Leave out city and location to spin for a random city,' telling the agent how to trigger the random path vs. a targeted one. There is no explicit when-not or named-alternative guidance, but no true alternative tool exists for building a day.

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