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. It adds useful context about secret variables not returning values in the response, which is a key behavioral trait. However, it doesn't cover other aspects like error conditions, permissions needed, or rate limits. The description doesn't contradict annotations (none exist), but it's incomplete for a read operation.

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 and well-structured: two sentences that directly state the purpose and a key behavioral constraint. Every word earns its place, with no redundancy or fluff. It's front-loaded with the main action, making it easy to parse quickly.

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 has no parameters, no annotations, and no output schema, the description is moderately complete. It explains what the tool does and a critical behavioral detail (secret variable handling), but lacks information on return format, error cases, or integration with sibling tools. For a simple read operation, this is adequate but has clear gaps.

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 0 parameters, and schema description coverage is 100% (empty schema). The description doesn't need to explain parameters, but it does mention '<CUSTOM_VARIABLE_NAME>' as a placeholder, implying the variable name is somehow specified (though not as a parameter). This slight ambiguity prevents a perfect score, but with no parameters, the baseline is high.

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: 'Shows the content of the custom variable with the name <CUSTOM_VARIABLE_NAME>.' It specifies the verb ('shows') and resource ('custom variable'), making it understandable. However, it doesn't explicitly differentiate from sibling tools like 'get_integration_webhooks_configuration_webhook' or 'create_integration_webhooks_configuration_custom_variables', which would be needed for a perfect score.

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 doesn't mention prerequisites (e.g., needing the custom variable name), exclusions, or related tools like 'update_integration_webhooks_configuration_custom_variable' or 'delete_integration_webhooks_configuration_custom_variable'. Usage is implied only by the action described, with no explicit context.

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