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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the safety profile is established. The description adds behavioral context by disclosing exactly what kind of content the search returns, including price trends and editorial summaries, which helps the agent set expectations.

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 with no filler. The first sentence states what the tool returns, and the second gives clear usage guidance, making the most important information immediately accessible.

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 that the annotations cover safety, the schema covers both parameters, and an output schema exists, the description is complete enough for an agent to select and invoke this tool correctly. It covers the tool's purpose, return content, and usage context.

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 100%, so the schema already documents both parameters fully, including examples and defaults. The description reinforces the intended use but adds no additional parameter-level meaning beyond what the schema provides.

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 verb 'Search' plus the resource 'neighbourhood and municipality guides for Portugal' is specific, and the description adds concrete output details: median price per m², price trend, and editorial summary. It also distinguishes itself from sibling tools by explicitly saying it is for area comparison rather than individual listings.

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 clearly states when to use the tool: when the user asks where to live or buy, or wants to compare areas. It gives a when-not signal ('instead of asking for individual listings'), though it does not name the specific sibling tool to use in that alternative case.

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