get_commute_advice

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

No annotations are supplied, so the description carries the full load. It does add genuine value by disclosing the data source (open GTFS via Transitous), the freshness caveat (live delays only where the operator publishes them) and the coverage limitation ('Coverage depends on the region'). It says nothing about failure behavior, rate limits, or what happens when a region is unsupported, which matters for a network-backed planning call.

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 core behavior is front-loaded in the first sentence, and the Args block is short and earns its place given zero schema coverage. The line-wrapping artifacts and the slightly redundant restatement of 'public-transport' in the Args block are minor waste.

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 an output schema present, return values need not be explained, and both required parameters are documented with examples. The behavioral summary plus the data-source and coverage caveats give an agent enough to call it correctly; only the region-coverage vagueness and lack of an explicit 'departs now / no time parameter' statement keep it from being fully 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 0%, so the description must supply the meaning, and it largely does: origin is defined as a station, landmark or address with a concrete example ('Orchard MRT, Singapore'), and destination gets its own example ('Changi Airport'). It does not clarify format expectations for ambiguous inputs or how geocoding ambiguity is resolved, which is the obvious remaining gap.

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+resource: 'Plan a public-transport trip leaving now ... recommend an option based on the current weather.' That clearly separates it from get_stop_departures (a departure board) and get_current_weather (weather only). It stops short of explicitly naming a sibling it is not, so it does not reach 5.

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?

'leaving now' implicitly tells the agent this tool is for immediate, present-moment trips rather than scheduled future journeys, and the weather-based recommendation hints at when to prefer it over a raw timetable lookup. But there is no explicit when-to-use/when-not guidance and no named alternative for the future-trip or stop-lookup cases.

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