maps_select_route

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

With no annotations, the description carries the full burden of behavioral disclosure, but it only mentions 'bounded Google Maps UI heuristics' without explaining what the selection actually does (e.g., highlights a route, prepares for summary, changes internal state). Side effects, reversibility, and error handling are not disclosed.

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 a single, concise sentence with no redundant words. It front-loads the core action and includes the key modifier 'zero-based index' without wasting space.

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 there is no output schema and no annotations, the description should explain what happens after selection and when to use it. It does not mention the return value, follow-up actions, or the effect of selection, making it incomplete for an agent that needs to invoke the tool 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 description explicitly clarifies the index parameter is zero-based, which is not evident from the schema's min/max values alone. It also ties the index to 'currently displayed route candidates', giving context. However, it does not explain edge cases like invalid indices beyond the schema's bound.

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 uses a specific verb ('Select') and identifies the resource ('currently displayed route candidates') and the selection mechanism (zero-based index). It clearly distinguishes from siblings like maps_select_result by narrowing to route candidates, and the 'bounded Google Maps UI heuristics' adds specificity.

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 phrase 'currently displayed route candidates' implies the tool should be used after routes have been generated, but there is no explicit when-to-use guidance or comparison with alternatives like maps_select_result. No exclusions or prerequisites are stated.

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