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 it mentions that the tool returns the updated metric object, it doesn't address critical behavioral aspects like required permissions, whether this is a destructive operation, rate limits, error conditions, or how 'specific' is determined (e.g., by ID). For a mutation tool with zero annotation coverage, this is a significant gap.

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 with just two sentences that directly state the tool's purpose and return value. There's no wasted language, and the information is front-loaded with the core functionality. Every sentence earns 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?

Given that this is a mutation tool (update operation) with no annotations, no output schema, and no parameters, the description is incomplete. It doesn't explain what constitutes a 'specific' metric (how identification works), what fields can be updated, what permissions are required, or potential side effects. The return statement is helpful but insufficient for a mutation operation in a complex system.

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 (schema description coverage is 100%), so there are no parameters to document. The description doesn't need to compensate for any parameter documentation gaps, and it appropriately doesn't attempt to describe non-existent parameters. A baseline of 4 is appropriate for zero-parameter tools.

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 ('Update') and the resource ('a specific span-based metric from your organization'), which provides a specific verb+resource combination. However, it doesn't distinguish this tool from sibling tools like 'update_apm_config_retention_filter' or 'update_logs_config_metric', which would require explicit differentiation.

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. There are many sibling update tools (e.g., update_apm_config_retention_filter, update_logs_config_metric), but the description doesn't mention any prerequisites, constraints, or when this specific metric update tool is appropriate versus other configuration updates.

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