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

Annotations already declare read-only, idempotent, non-destructive behavior, so the bar is lower. The description still adds real value beyond them: every output line carries its type (data/rule/sum/user figure), source and read date, and it explicitly states the tool never concludes whether to move. No rate limits or auth needs are mentioned, but they are irrelevant for a local calculator.

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?

Content is front-loaded with the balance of moving and every clause describes a distinct output line, so little is wasted. However, the identical text is repeated verbatim in Spanish, doubling the length without adding information for the agent.

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?

With 18 params at 94% coverage and no output schema, the description effectively serves as the output description, enumerating return lines and their metadata, and states the tool's non-recommendation boundary. This is nearly complete; only explicit sibling routing is missing.

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 94%, so the schema already documents the 18 parameters. The description ties them to the calculation model (user figures override official averages) but adds little per-parameter 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 description states a specific verb+resource: it computes the balance of moving between two municipalities in the Barcelona area, enumerating the exact figures produced (rent+IBI, ITP, notary/registry, m² bought, recovery months, commute time). This clearly distinguishes it from generic comparison siblings. It does not, however, explicitly name any sibling (e.g. comparar_municipios) to differentiate.

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?

Usage is only implied: the framing 'Is moving worth it?' and the note that official averages can be replaced by user figures signals the evaluate-a-move scenario. There is no explicit when-to-use vs alternatives guidance and no exclusion rules routing to the 13 sibling tools.

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