Stats

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavior: a fixed one-hour lookback window, cross-tenant/cross-account data scope, and an account-level enablement gate that surfaces as HTTP 403 — all things the agent cannot infer from 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?

Three compact sentences, front-loaded with the resource and scope before the caveats. The opening "Stats." is pure redundancy with the title and could be cut, but nothing else is padded.

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?

For a read-only, two-optional-parameter tool this covers scope, time window, and the activation failure mode well. However, with no output schema, the description never hints at what metrics come back (latency, error rate, uptime), leaving the agent unable to judge whether the response answers its question.

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%, so both parameters are already fully documented including the engine/path pairing rule and an example path. The description only reinforces that the tool targets "an engine or endpoint" without adding syntax, defaults, or precedence rules beyond the schema, so the baseline 3 applies.

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?

"Infrastructure health for an engine or endpoint over the last hour" names a specific resource (health metrics), a target dimension (engine or endpoint), and a time window, which distinguishes it from the search-oriented siblings. The leading "Stats." merely restates the title and adds nothing, keeping it 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?

The line "Not scoped to your account or tenant" implicitly routes account-level questions to the sibling `usage` tool and tells the agent this is system-wide telemetry. It also gives concrete operational guidance for the 403 case, though it never states the positive trigger (e.g. diagnosing errors or latency) or names an alternative explicitly.

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