List your monitors

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

The readOnlyHint annotation already signals safety, and the description adds useful behavioral detail by naming the delivery health fields returned (last fired, failures, active). It does not contradict annotations and gives the agent a concrete sense of what the operation reports.

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, well-structured sentence immediately states the resource and API-key scope, then adds the most useful output detail. Every word earns its place and there is no redundant phrasing.

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 zero-parameter, read-only list tool, the description covers the key information: what is listed and what health attributes are exposed. It does not fully spell out the exact return shape or possible pagination, but the lack of parameters and the simple listing nature keep this gap minor.

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 and the schema coverage is effectively complete, so there is nothing for the description to clarify. The baseline of 4 applies, and the description appropriately avoids inventing parameter-related guidance.

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 states a specific verb and resource: listing monitors. It also adds scope ('on your API key') and a meaningful detail about what is included (delivery health), which clearly distinguishes it from sibling list tools like list_sources and list_datasets.

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 provides clear context: this tool is for viewing monitors tied to the caller's API key, including their health status. It does not explicitly mention when not to use it or name alternatives, but the resource-specific wording makes the appropriate use case evident.

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