List routes

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

Annotations already declare readOnlyHint=true, so 'Read-only' largely repeats structured data. However, the description adds genuinely useful context beyond annotations by describing the per-route payload (id, description, visibility, distance in m, start/end coordinates, waypoint count), compensating for the absence of an output schema.

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 short sentences, none wasted: purpose, return shape, and routing to the sibling tool, with the primary purpose front-loaded. Optimal size for a simple list operation.

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?

With no output schema, describing the returned route fields is exactly the right compensation and is done here. The only minor gap is absence of pagination/volume hints for an 'all routes' call, but overall the definition is complete enough to call correctly.

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 tool takes no parameters, so there is nothing to disambiguate; baseline for a zero-parameter tool is 4. No parameter-related confusion is possible here.

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 ('Returns all routes'), the resource, and the scope ('saved in the user's Suunto account'), then enumerates the returned fields. It is immediately distinguishable from siblings like export_route without needing 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?

Explicitly routes the agent to the right alternative: 'Use export_route to get the GPX track for navigation,' making the boundary between listing and exporting clear. No explicit when-not guidance is given, but the alternative is named with its triggering condition.

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