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

Annotations already communicate readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds useful behavioral context beyond that: the returned routes are restricted to those Ourway sells, the list includes slug/name/total km, and it is the required starting point for itinerary construction. No contradictions with annotations are present.

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 front-loaded with the main purpose and well structured, but it is bilingual and repeats much of the same content in Spanish, which adds length without new information for an English-reading agent. The usage guidance and parameter documentation are valuable, yet the redundancy prevents a higher conciseness score.

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?

The tool has a rich annotation set, an output schema, and only one optional parameter, so the description does not need to explain return structures in depth. It adequately covers what the tool lists, why to use it, what the parameter values mean, and how it relates to plan_camino_itinerary. An agent has enough context to decide when to call it and what to pass.

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 0% and the schema itself only shows a default without explaining the parameter. The description compensates by documenting `tipo` values with human-readable meanings: a_pie (walking), en_bicicleta (cycling), a_caballo. It does not explicitly state that `tipo` filters the returned routes or that a_pie is the default, but it provides the essential semantic coverage the schema lacks.

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 opens with a specific verb and resource: 'List the Camino de Santiago routes Ourway sells and can book.' It enumerates concrete route examples and expected output fields (slug, name, total km), and distinguishes itself from the sibling plan_camino_itinerary by stating that the bookable itinerary is built there. This makes the tool's role immediately identifiable.

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 'Start here for any Camino de Santiago trip question' with sample queries, establishing when to reach for this tool. It also names the alternative for the next step ('El itinerario reservable lo construye plan_camino_itinerary') and clarifies that only the listed routes are reservable, which tells the agent when this tool is the authoritative source.

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