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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds valuable context: no auth required, rate limit of 100 req/min, and the data source (community HAFAS wrapper for BVG). This goes beyond the annotations and helps the agent understand operational constraints.

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 with the core purpose, followed by the example, output usage, and operational details. Every sentence earns its place, and the data source/rate limit info is efficiently appended without bloating the description.

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?

The description covers the tool's purpose, output, downstream usage, data source, auth, and rate limits. With an output schema present and full parameter documentation, this is nearly complete. The only minor gap is not explicitly stating that results are limited to Berlin/Brandenburg, though that is mentioned in the first sentence.

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 the schema already documents all four parameters thoroughly. The description adds the example query format and clarifies the purpose of results (location IDs for downstream tools), but doesn't add significant meaning beyond the schema. Baseline 3 is appropriate.

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 states the tool searches for transit stops, addresses, and POIs in Berlin/Brandenburg by name, with a concrete example. It explicitly mentions the output (location IDs and coordinates) and how they connect to other tools (departures, journey planning, nearby-stop lookups), distinguishing it from generic geocoding tools.

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 description provides clear context for when to use this tool (searching by name for transit locations) and mentions its role in downstream workflows. It doesn't explicitly exclude alternatives like nearby_stops or plan_journey, but the sibling list shows related transit tools and the description implies this is the entry point for location discovery.

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