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

The description discloses key behavioral traits beyond annotations: 'batched by chamber side to minimize cross-campus crossings,' 'route + minutes between each stop,' 'cross-campus window flagged,' 'leave-by times,' and 'warnings for connections too tight to make.' Annotations already declare readOnlyHint and openWorldHint, and the description adds rich behavioral context without contradiction.

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?

The description is two sentences: the first clearly states the purpose and input requirements; the second details the output features. It is concise, front-loaded, and earns its sentences with high information density.

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?

Given the complexity of multi-meeting planning and the lack of an output schema, the description provides a thorough overview of what the tool returns: sequenced itinerary, batching, travel times, warnings, and leave-by times. This is sufficient for an agent to understand the tool's output without needing an output schema.

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?

The description adds meaning beyond the input schema: it explains that 'who' can be a member name or room code, and provides an example time format ('10:30a'). It also mentions the optional 'accessible' parameter indirectly via 'plan step-free routes' in the schema. While the schema covers basic types, the description enriches understanding of usage.

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 description clearly states the tool's purpose: 'Optimize a multi-meeting Hill day.' It specifies the input (list of meetings) and detailed output (itinerary with routing, warnings, leave-by times). It distinguishes itself from siblings like route_between (single route) and accessible_route (step-free routes only) by focusing on multi-meeting optimization.

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 description implicitly indicates when to use this tool: when you have multiple meetings to schedule. It mentions the input format and what the tool returns, but does not explicitly state when not to use it or compare to alternatives. However, the context from sibling names (e.g., route_between) helps differentiate.

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