rds_metrics

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

The description declares the tool 'Read-only' and lists the metrics it retrieves, giving a clear picture of its behavior. With no annotations provided, it adequately covers the read-only nature and scope, though it could mention that it uses CloudWatch API calls and potential permissions needed.

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 extremely concise: two sentences that first state the purpose and metrics, then provide usage context and a parameter note. No unnecessary words, and the most important information comes first.

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?

The description is complete for a simple snapshot tool: it lists the retrieved metrics, notes read-only access, and provides a specific use case. It does not mention error conditions or pagination, but those are less critical for a tool that likely returns a single snapshot. Overall, it covers the essential context well.

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 has 100% description coverage for all three parameters, each clearly documented. The description adds only a restatement of the 'db_instance' parameter meaning, adding no extra semantics beyond what the schema already provides. Baseline score of 3 is 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 clearly states the action (snapshot) and resource (RDS instance health metrics) and specifies the exact metrics: CPU, connections, CPU credit balance, read/write latency, freeable memory. It also identifies it as the first check for the shared-RDS noisy-neighbour case, distinguishing it from sibling tools.

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 indicates the tool is the 'first check for the shared-RDS noisy-neighbour case,' implying a specific diagnostic scenario. While it provides clear context, it does not explicitly state when not to use it or list alternatives, leaving some ambiguity.

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