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

Annotations already declare this a safe, read-only, idempotent operation, so the safety profile is covered. The description usefully adds data-scope constraints (Jan.-June 2026 vintage, pesos available by state only, index by state or municipality), which is genuine behavioral context. It does not describe return format or limits, so it adds moderate rather than rich value beyond the 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?

A single front-loaded sentence leads with the country and source, then enumerates the returned metrics and the geographic granularity. No filler. It packs several facts into one sentence, which borders on dense but stays readable.

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 no output schema, the description carries the return-value burden and does so adequately by naming the metrics, units, and geographic breakdown. Annotations handle safety. The main omission is period/coverage caveats beyond the stated Jan.-June 2026 window, but for a single-parameter lookup tool this is fairly complete.

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% and the single 'place' parameter is fully documented in the schema (including empty = national). The description mentions state/municipality scope, but the subtle detail that peso prices exist by state only is not tied explicitly to the parameter, so it adds little beyond the schema. Baseline 3 for high 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 names a specific source (Sociedad Hipotecaria Federal) and states exactly which metrics are returned: median/mean appraisal value by state and the year-over-year price index change by state or municipality. It is clear what an agent gets back. It does not explicitly differentiate itself from siblings like house_prices_* or compare_states_mx, so it stops short of a 5.

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 implied by the content (query Mexican SHF appraisal/index figures) but there is no explicit when-to-use, when-not-to-use, or named alternative among the many sibling price tools. An agent can infer the domain but must guess how this differs from compare_states_mx or the country price tools.

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