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

Annotations give readOnlyHint=true and openWorldHint=false, so safety is covered. The description goes further by disclosing that results are cached and that prices are indicative, not final, plus the 180-day horizon. It omits pagination/truncation behavior, but the freshness caveat is exactly the kind of extra behavioral context this dimension rewards.

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?

Four short sentences, each earning its place: what it returns, freshness caveat, cross-reference, and scope hint. Front-loaded with the payload 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?

For a read-only, no-output-schema tool, the description covers return shape (daily rows + indicative prices), freshness, range limit, and the sibling to use for firm pricing. Slightly short on the cache TTL and whether long ranges are truncated, but complete enough to call correctly.

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 only 33% (only 'to' is documented as exclusive). The description compensates by establishing the 180-day range horizon and the day-by-day granularity, which explains how from/to are interpreted. property_id remains undocumented, but the added range semantics go meaningfully beyond the thin schema.

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, resource and granularity: day-by-day availability plus indicative prices over a bounded 180-day window, and even names the underlying HTTP endpoint. An agent can distinguish this from get_quote and get_property without inspecting the 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?

Explicitly routes the agent: use this for flexible dates, use get_quote to confirm prices. Names the alternative and the condition that selects it, so the choice between browsing and quoting is unambiguous.

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