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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety/repeatability is covered. The description adds useful context about what the record contains (photos, energy rating, seller, source URL) but doesn't disclose any additional behavioral traits such as error cases or rate limits. No contradiction with annotations.

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, front-loaded with purpose and followed by a useful usage condition. The field list is compact and earns its place by telling the agent what to expect in the returned record.

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 single-parameter read-only tool with a full output schema and annotations, the description covers what remains important: when to call it, what it returns, and how it relates to search_properties. No critical missing context for correct invocation.

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 100% and the single parameter is already described as 'Unique listing slug, as returned by search_properties.' The description reinforces that the slug comes from search_properties but adds no new semantic detail beyond the 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 clear verb ('Get') and a precise resource: the complete record of one listing in Portugal by slug. The description also distinguishes this from search-oriented siblings by naming search_properties as the prerequisite and clarifying this is for a specific property.

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 guidance: use after search_properties when the user asks about a specific property. It doesn't enumerate when-not-to-use alternatives like find_similar_properties or search_properties_by_description, but the stated condition is clear enough for an agent to route correctly.

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