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 does disclose that the operation returns paginated data and supports date-range filtering, which are useful behavioral traits, but it does not mention any constraints, error cases, or permission requirements. Since this is a read operation, the absence of mutation side effects is less critical, but more detail would be needed for full transparency.

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 primary action and resource, and every clause adds relevant information. It is appropriately sized without unnecessary detail.

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 7 parameters, 5 required, no output schema, and no annotations, the description should provide a clear picture of the returned data. It mentions paginated time-series data and filtering but does not describe the structure of the data points or any default behaviors beyond what the schema states for parameters. The description is adequate for a straightforward read tool but leaves gaps about response format.

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 100% description coverage for all 7 parameters, so the baseline is 3. The description adds context about pagination and date-range filtering, which align with page/pageSize and startDate/endDate, but it does not add new meaning beyond the schema descriptions.

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 retrieves custom metric data points for an entity, specifies it returns paginated time-series data for a specific custom metric, and mentions optional date-range filtering. However, it does not explicitly differentiate from sibling tools like getCustomDataForEntity or queryPointInTimeMetrics, so it stops short of perfect clarity.

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 implies usage for analyzing trends and patterns with optional date-range filtering, which gives some context. However, it does not provide explicit when-to-use guidance, exclusions, or alternatives among the many sibling tools, so the agent must infer the appropriate tool.

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