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

Annotations already signal readOnly, idempotent, and non-destructive behavior, and the description adds substantial behavioral context beyond that: history matching is attempted against DSEC's general statistics database, it only succeeds for some series, gaming revenue notably has no general-catalog counterpart, and a null history is accompanied by an explanatory note. This is transparent and goes far beyond what the annotations provide.

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 front-loaded with the core purpose and every substantive behavioral detail earns its place. It is fairly long because the tool has conditional history-matching behavior, but the final sourcing sentence adds only marginal value and the long parenthetical could be tightened.

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 does a good job of explaining the key return behaviors: current value, reference period, unit, optional history, and history_note. It does not cover invalid inputs, ambiguous name matches, or what happens when neither id nor name is passed, which are meaningful gaps for an open-world tool with fuzzy keyword matching.

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%, so the baseline is 3, but the description adds meaningful semantics: id comes from macau_indicators, name accepts English/中文/Portuguese keywords, and periods defaults to 24 and only applies when a general-catalog match exists. One minor issue is that the description implies at least one of id/name should be provided while the schema marks all parameters as optional, leaving the no-argument case unclear.

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 clearly states a specific verb, resource, and scope: it returns the latest published value for Macau's DSEC key indicators, optionally with history. It does not explicitly differentiate itself from sibling tools like macau_gaming_revenue or macau_population, though it references macau_indicators as the source of IDs. This is strong but stops short of the explicit sibling differentiation that a 5 would require.

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 gives clear usage context: pass an id or name, and use periods to attempt a historical series. It provides meaningful conditional behavior (when history is unavailable, history is null and history_note explains why), but it does not explicitly say when to choose this tool over specialized siblings or when to avoid it.

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