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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real value by disclosing the returned metric set, which matters because there is no output schema. It stops short of saying whether figures are a live snapshot, whether slow-query data depends on query-stat extensions, or whether the call is expensive on large instances.

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 short sentence with zero filler, and the most useful content (the metric list) is front-loaded. It is a noun-phrase fragment with no verb, so it reads as a title extension rather than a self-contained instruction.

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 is the only source of return-value information, and it does enumerate the metrics an agent will receive. For a one-parameter read-only tool with full schema coverage that is largely sufficient, though the absence of any usage or freshness context leaves a small gap.

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% and the single 'id' parameter already documents its origin ('from list_services'), so the schema carries the burden. The description adds nothing about the parameter, leaving the baseline of 3 appropriate.

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 enumerates exactly which metrics are returned (size, connections in use, cache hit rate, largest tables, slowest queries), which makes the vague word 'stats' concrete and distinguishes it in substance from get_database_schema or run_sql. It lacks a verb and never names a sibling, so the differentiation is implicit rather than stated.

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?

There is no when-to-use guidance at all: nothing says to prefer this over get_database_schema for structure, over run_sql for custom metrics, or that it is a read-only health-check tool. No prerequisites, exclusions, or cost/latency warnings are given.

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