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

Annotations already cover read-only/idempotent/non-destructive, but the description goes well beyond them: it explains the recording rule (first time anyone opens the Status screen in a month), why missing months are absent rather than zero, that actual is null when there was no data, the distinction between base_target and derived_target, and the status vocabulary. This is exactly the behavioral context annotations cannot carry.

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 purpose and read-only framing are front-loaded, and the dense middle paragraphs are packed with non-redundant semantics (units, target meaning, null handling). It is a long single paragraph, but nearly every clause earns its place, so only minor marks off for readability.

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?

There is no output schema, so the description must explain the returned shape, and it does: it documents each field (actual, base_target, derived_target, status), the units for fci, asset_past_useful_life_pct, asset_condition_avg and risk_score_avg, and explicitly warns that none of the values are money. Nothing needed to interpret results 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?

With 100% schema description coverage, the schema already documents all eight parameters and the metric enum, so 3 is the baseline. The description adds only mild value by grouping the filterable dimensions and noting the range is compared to period_start; it omits page/per_page behavior entirely, which the schema does state.

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 specific verb and resource ('List monthly technical Level of Service readings, newest first') and clarifies scope (one reading per tracked pair and metric per month). It is clearly distinguishable from the singular get_los_status_snapshot by the 'List' framing and monthly granularity, though it never names the sibling explicitly, so it falls just short of 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?

The description ends by enumerating the filters ('Filter by system, building, network, metric, or a period range on period_start'), which implies how to narrow results, but it never says when to reach for this tool versus get_los_status_snapshot or list_los_measurements. Usage is implied rather than stated.

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