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

With no annotations, the description carries the behavioral burden. It discloses that results are currently filling cars, that the radius is approximately 2.5 km, that driver-opened cars at stations are listed first, and that the returned share URL lets the rider join. This is meaningful behavioral detail, though it does not discuss empty-result behavior or data freshness.

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 compact and front-loaded: the first sentence conveys the core action and output fields, the second covers ordering, and the third states the required inputs. Every sentence earns its place with no filler.

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?

Although there is no output schema, the description enumerates the return fields and includes the share URL pattern, which tells an agent what to expect. It also covers scope, radius, ordering, and required parameters, making the tool effectively invokable without external context.

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 100%, so baseline is 3. The schema already documents lat and lng as Latitude and Longitude with bounds; the description adds only 'point in Addis Ababa' and the radius, which is helpful but not a deep parameter-level explanation.

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 clearly specifies the verb context and resource: it returns BinaPool cars currently filling near a point, with destination, seats left, seat price, women-only flag, and a share URL. This is distinct from siblings like list_pool_corridors, which concern corridors rather than live filling cars.

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 'within about 2.5 km of a point in Addis Ababa' gives a clear geospatial condition, and 'Requires lat/lng' states the prerequisite. It does not explicitly name alternatives or say when not to use it, so it misses a full 5.

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