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 of behavioral disclosure. While 'Retrieves' implies a read-only operation, the description doesn't specify whether authentication is required, what happens if no schedule exists, whether there are rate limits, or what format the returned user information takes. For a tool with zero annotation coverage, this leaves significant behavioral gaps.

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 a single, efficient sentence that gets straight to the point without any wasted words. It's appropriately sized for a simple retrieval tool and front-loads the core functionality.

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 tool with zero parameters, no annotations, and no output schema, the description provides the basic purpose but lacks important context. It doesn't explain how schedules and times are specified without parameters, what the return format looks like, or any error conditions. The description is minimally adequate but leaves the agent guessing about implementation details.

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 with 100% schema description coverage, so the schema already fully documents the parameter situation (none). The description mentions 'specified schedule' and 'given time' which might imply parameters, but since there are none, this creates some confusion. However, with zero parameters, the baseline is 4 as the description doesn't need to compensate for missing parameter documentation.

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 ('Retrieves') and resource ('user who is on-call for the specified schedule'), making it easy to understand what it does. However, it doesn't differentiate from sibling tools like 'get_on_call_schedule' or 'get_on_call_team_on_call', which appear to be related on-call tools in the sibling list.

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. It mentions 'specified schedule' and 'given time' but doesn't explain how these are specified (since there are zero parameters), nor does it mention any prerequisites, constraints, or when to choose this over other on-call related tools in the sibling list.

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