fleet_status

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

Annotations already mark it as read-only and non-destructive, and the description goes further by adding 'Read-only, pure; no device I/O,' explaining the offline logic based on stale_after_s, and clarifying that fleet_status is the worst site status present. This adds valuable behavioral context beyond the structured 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?

The description is well-structured with clear Args, Returns, and Example sections. Every sentence adds value—no filler—and the length is justified given the need to document three parameters and return semantics in the absence of schema descriptions.

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?

Despite no output schema, the description lists the return dict keys and explains the input behavior and output structure. It also provides an example, making the tool self-contained and fully understandable for an agent to select and invoke correctly.

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?

The schema provides no parameter descriptions (0% coverage), but the description fully compensates. It details the sites argument structure including optional fields and status values, defines stale_after_s with its default, explains now as an optional ISO-8601 timestamp for deterministic staleness, and even includes a usage example.

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 the tool's function: 'Roll up per-site status reports into one fleet health view.' It also differentiates itself from sibling data_quality_fleet_rollup by noting it aggregates across edge SITES rather than per-endpoint within one site, making its purpose distinct.

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 explicitly positions this tool as 'the tier above data_quality_fleet_rollup' for central management across sites, giving clear context for when to use it. However, it does not explicitly state when not to use it or mention alternatives beyond that one sibling, so it stops short of full exclusionary guidance.

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