health_get_exercise_route

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

With no annotations, the description carries the full burden and does so well: it discloses the GPS-only precondition, that routes are fetched per sync window, that TCX payloads can reach hundreds of kilobytes, and that the heavy payload is opt-in via include_tcx. That size/opt-in behavior is exactly the kind of trait an agent needs before calling.

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?

Front-loaded with the core action and format, then supports it with preconditions and payload caveats. Slightly long, and the 'Returns' sentence partly duplicates the output schema, but every sentence adds usable context.

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 a small two-parameter tool with an output schema already defining the return shape, the description covers precondition, payload size risk, and opt-in behavior. Nothing an agent needs to call it correctly 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 0%, so the description must compensate, and it documents both parameters: log_id with its cross-reference to health_get_exercises, and include_tcx with its default-off implications. Nothing about invocation is left to guess.

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 and resource ('Get the GPS route of one exercise') and pins the format ('as the TCX file Google exports'). It is clearly distinct from health_get_exercises, whose log_id it consumes, so an agent can route between the two without opening schemas.

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?

Gives clear context: only GPS-recorded exercises have a route, sync scope determines route availability, and the TCX is returned only when include_tcx is set. It names the prerequisite source (health_get_exercises) but does not explicitly say when to prefer this over sibling reads like health_get_exercises.

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