get_journey_time

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

No annotations are provided, so the description carries the full burden and adds almost nothing: it doesn't say whether the time is real-time or scheduled, whether disruptions are factored in, what units are returned, or whether it covers buses/trains. For a lookup whose value hinges on those traits, this is a significant gap.

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?

A single front-loaded sentence with no filler. Nothing is wasted.

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 and no annotations, the description should at minimum describe what the returned time represents (units, mode, real-time vs planned). It also fails to position the tool against plan_journey, so an agent lacks enough to invoke it confidently in this crowded transit toolset.

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 coverage is 100% and both parameters are documented as 'Starting location' and 'Destination'. The description only restates 'two locations' without adding format hints (station names, codes, coordinates), so the baseline 3 applies.

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 fastest journey time between two locations'. It is clear what the tool returns and requires two endpoints, but it never distinguishes itself from the sibling plan_journey, which an agent could easily pick instead for the same query.

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?

There is no guidance on when to use this rather than plan_journey, get_fare, or get_arrivals. The description gives no prerequisites, no transport-mode context, and no exclusions, leaving routing entirely to inference from the name.

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