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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and openWorld, so the safety profile is covered. The description adds real behavioral detail beyond that: results are ordered nearest-first and carry a distance in metres, and the coverage is limited to TTC stops in Tbilisi. It does not mention behavior at radius boundaries or empty results, but the output schema covers return shape.

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?

Two sentences, both load-bearing: the first defines the operation, scope and result format, and the second supplies the prerequisite for getting coordinates. Nothing is redundant and the core behavior is front-loaded.

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, full annotation coverage and a fully documented parameter schema, the description only needs to establish scope and the input-acquisition path, both of which it does. The geographic restriction to Tbilisi and the TTC operator scope are stated so an agent will not expect coverage elsewhere.

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%, with every parameter including kind values, limit range and default, language codes, and radius range and default documented in the schema itself. The description only reinforces the distance concept via 'within a distance' and the metres unit; it adds no syntax or semantics the schema lacks. 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?

The description gives a specific verb and resource ('Lists the stops of the TTC'), plus the spatial scope (within a distance of a point in Tbilisi) and result ordering (nearest first). It is clear what the tool produces, but it never distinguishes itself from the sibling transit_search_stops, which an agent could easily confuse with a proximity listing.

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?

It states the context of use and names transit_search_places as the way to obtain the required coordinates, which is a genuine workflow hint for an agent that only has a place name. It stops short of explicit exclusions, saying nothing about when to prefer transit_search_stops (name-based lookup) or transit_get_route instead.

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