List Monitors

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds that this retrieves all monitor configurations from Mackerel, but it does not disclose pagination behavior, return shape, authentication needs, or rate limits. For a simple read-only list tool this is adequate, but it goes only modestly beyond the annotation.

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 core sentence is front-loaded and clear, but the use-case bullets largely restate the purpose, and the example adds little value for a zero-parameter tool. It is not bloated, but some content does not earn its place.

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?

This is a simple zero-parameter read-only list operation with an annotation covering safety. The description is sufficient for an agent to invoke it correctly, though it omits pagination and return-format details that could matter for a list endpoint.

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 tool has zero parameters, so there are no parameter semantics to explain. The empty schema is fully self-describing, and the description does not need to compensate for undocumented parameters.

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 a specific verb and resource: retrieve all monitor configurations from Mackerel. It implies a list-all operation, which helps distinguish it from the singular get_monitor sibling, though it does not explicitly name that sibling or contrast the two.

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 'USE THIS TOOL WHEN USERS' section gives clear use cases: getting a list of all monitors and viewing monitor configurations. It does not provide exclusions or explicitly route users to get_monitor for a single monitor, so it lacks full when-not/alternatives guidance.

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