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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral facts: results are public listing summaries containing a link to each listing page, and dealer names plus exact prices are withheld by design — a data-availability constraint an agent could not infer from annotations or schema.

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?

Three short sentences with no redundancy: scope first, filter capabilities second, return shape and routing constraint third. Every sentence carries information the agent needs, and the limitation on dealer names is placed where it prevents a wasted call.

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, the description correctly specifies what comes back (public listing summaries plus a listing link) and flags the withheld fields. All seven optional parameters are documented in the schema, including the 25-result cap. Minor gap: no mention of how results are ordered or whether totals are returned, which matters for an all-optional search.

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 86%, so the schema documents nearly every parameter including examples for state, bus_type, min_seats and limit. The description's filter list largely restates those fields and omits the free-text `query` parameter entirely, adding no format or matching semantics beyond what the schema already provides. 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 with scope: 'Search the commercial buses currently listed for sale by participating dealers.' It also names the boundary of that data and routes dealer contact to request_bus, so an agent can separate it from get_bus and list_bus_categories without opening a schema.

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 enumerates the five filter dimensions that drive a search (type, seats, wheelchair lift, condition, state) and explicitly names request_bus as the follow-up when a dealer must be reached. It gives no guidance on choosing between this and get_buying_context or on narrowing when results are empty, so it stops short of full when/when-not coverage.

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