Route between places

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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is well covered. The description adds context beyond annotations: it specifies the data source (OpenStreetMap), the order-fixed behavior, and the optional turn-by-turn steps via include_steps. No contradictions; the added behavioral detail is useful but not exhaustive (e.g., no mention of network assumptions or error cases).

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?

Two sentences with zero redundancy. The core action is front-loaded, the order constraint is stated, and the sibling routing is given at the end. Every sentence 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?

An output schema exists, so return format details are not required in the description. The tool handles 2–25 waypoints with fixed order, multiple profiles, and optional steps—all key behaviors are covered. It lacks mention of coordinate format (but schema covers that) and doesn't discuss error cases, but given the annotations and schema coverage, it is adequately complete.

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 parameters. The description adds meaning by clarifying that waypoints are visited in order (schema says 'Start, optional stops in between, destination' but description makes it explicit) and that include_steps provides a turn-by-turn summary, which reinforces the schema's boolean description. This goes slightly beyond the 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?

The description clearly states the tool computes real-world travel distance and time between two or more places using walking, driving, or cycling on OpenStreetMap data. It distinguishes itself from siblings by explicitly naming route_matrix (compare many pairs) and optimize_route (reorder stops), so an agent can tell them apart without opening the schema.

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 explicitly says 'Use route_matrix to compare many pairs, optimize_route to reorder stops,' providing clear when-not-to-use guidance. It also implies this tool is for a single route with a fixed order, which is directly stated by 'Waypoints are visited in the given order.' This gives an agent explicit routing logic for selection.

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