MCP Datadog Server

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

No annotations are provided, so the description carries the full burden. It discloses that the tool is a read-only endpoint (implied by 'returns') and defines behavioral traits like time-based criteria for 'active' and 'up', which is useful context. However, it doesn't mention rate limits, authentication needs, or response format, leaving gaps in behavioral disclosure.

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 two sentences, front-loaded with the main purpose and followed by clarifying definitions. Every sentence adds essential information without waste, making it efficient and well-structured for quick understanding.

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?

Given the tool's low complexity (0 parameters, no output schema), the description is reasonably complete for a simple read operation. It explains what the tool does and defines key terms, but lacks details on output format (e.g., JSON structure) and any limitations, which could be helpful for an agent despite the absence of an output schema.

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 input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description appropriately focuses on the tool's purpose without redundant param info, earning a baseline 4 as it adds value beyond the schema by explaining what the tool returns and the definitions of 'active' and 'up'.

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 tool's purpose with a specific verb ('returns') and resource ('total number of active and up hosts'), and distinguishes it from siblings by specifying it's about host totals rather than other metrics like logs, monitors, or integrations. It also defines key terms ('active' and 'up') to clarify scope.

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 no guidance on when to use this tool versus alternatives, such as other host-related tools (e.g., 'get_hosts' for detailed host lists) or sibling tools for different data types. It lacks explicit when/when-not instructions or named alternatives, leaving usage context implied at best.

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