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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds meaningful behavioral context: 'Data is live from the property management system' and clarifies this is the data-only variant, including what the caller should do before rendering. These add value beyond the annotations without contradicting them.

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 well-structured and front-loaded: purpose and return fields first, then live-data context, then alternative routing, then Args. Every sentence adds necessary information; there is no filler or redundancy.

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 simple read-only lookup with no output schema, the description is complete: it states the return fields, data source, parameter semantics, and the relationship to the gallery-rendering sibling. An agent has enough information to invoke this tool correctly and decide next steps.

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?

The schema has 0% description coverage and only lists default values, so the description carries full responsibility. It compensates thoroughly: explains each parameter, gives concrete examples ('11', '15', '#12', 'all'), documents the empty-as-all behavior, and enumerates language values with default and usage guidance.

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 ('Get details') and resource ('apartments at Landhaus Prägant, Bad Kleinkirchheim, Austria'), and explicitly lists returned fields (size, bedrooms, amenities, highlights, cleaning fees). It also distinguishes itself from the sibling render_apartment_gallery by calling itself the 'data-only version'.

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?

Gives explicit routing guidance: use this for data, then call render_apartment_gallery() with the same arguments for a visual card. Also instructs to match the language parameter to the conversation language, which is a clear usage rule.

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