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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds value by explicitly stating 'It never reserves, charges, creates an intention or modifies data' and by describing the conditional availability/checkout URL behavior. This goes beyond the annotations and clarifies what the tool does and does not do during execution.

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, no wasted words. The first sentence fronts the core purpose; the second adds a conditional behavior and a strict safety statement. Every phrase earns its place with high information density.

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?

Given the tool has an output schema (not detailed here), the description need not explain return format. It covers the read-only nature, optional parameters, and safety profile. It could mention the language parameter or explicitly note that a houseCode is required, but the core usage is adequately described for an agent to call it 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 17% (only houseCode has a description). The description mentions 'dates and guests' but does not map these to specific parameters (checkIn, checkOut, adults, children) or explain the language enum. It adds some context—that supplying these values triggers availability—but does not sufficiently compensate for the low schema coverage.

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 states a specific verb (Get) and resource (property details) with an optional 'date-bound price,' clearly distinguishing it from list_destinations and search_homes. It centers on a single property (houseCode) and adds conditional pricing behavior, leaving no ambiguity about the tool's core purpose.

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 gives a clear condition—'When dates and guests are supplied, returns a server-side availability result plus a direct checkout URL'—but does not explicitly exclude alternatives or say 'use this when you already have a houseCode.' Context implies it is for a specific property, but explicit sibling differentiation is missing.

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