MCP Datadog Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure but offers minimal information. 'Update' implies a mutation operation, but the description doesn't specify what permissions are required, whether the update is reversible, what happens to existing key usage, or what the response contains. For a mutation tool with zero annotation coverage, this leaves critical behavioral aspects undocumented.

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 ('Update an API key') but this brevity comes at the cost of being under-specified rather than efficiently informative. While it's front-loaded with the core action, it lacks the additional context needed for a mutation tool. The single sentence doesn't waste words but fails to provide adequate guidance.

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 mutation tool with no annotations, no output schema, and no parameters, the description is incomplete. It should address behavioral aspects like authentication requirements, side effects, error conditions, and what constitutes a successful update. The current description provides only the most basic functional statement without the context needed for safe and effective use.

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% description coverage, so there are no parameters requiring semantic explanation. The description doesn't need to compensate for any parameter documentation gaps, making a baseline score of 4 appropriate for this zero-parameter scenario.

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 'Update an API key' is a tautology that restates the tool name without adding meaningful specificity. It provides a basic verb+resource but lacks any detail about what aspects of an API key can be updated (e.g., name, permissions, expiration) or how this differs from related operations like creating or deleting API keys.

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's no mention of prerequisites (e.g., needing an existing API key to update), when this operation is appropriate versus creating a new key, or how it relates to sibling tools like 'create_api_keys' and 'delete_api_key' that appear in the list.

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