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

Beyond the annotations (readOnlyHint, openWorldHint, idempotentHint, destructiveHint), the description adds meaningful context: it is self-aggregating, derived from CF analytics-engine, contains no PII, and is cached for 5 minutes to 1 hour depending on window. These details enhance understanding of the tool's behavior without contradicting the annotations.

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 three sentences with a clear, front-loaded statement of functionality, followed by a structured 'Useful for' list and a succinct note on data source and caching. Every sentence contributes value, with no filler or redundancy.

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?

Although there is no output schema, the description explicitly states the return contents (top tools, top packs, total call volume, and the format '(pack, tool, count)'), addresses privacy ('no PII'), and notes caching behavior. For a simple, single-parameter tool with comprehensive annotations, this is complete enough for an agent to invoke it correctly.

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 schema description already covers the 'window' parameter fully (100% coverage), including the default and the interpretation of shorter vs longer windows. The description itself merely repeats the window options and does not add new semantic meaning, so it meets the baseline of 3 but does not exceed it.

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 what the tool does: 'Returns the top tools, top packs, and total call volume over a recent window.' The verb 'returns' and specific resources make it distinct from sibling tools like discover_tools or recent_alerts, fulfilling the specific verb+resource criterion.

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 three explicit 'Useful for' scenarios: discovering hot data sources, confirming canonical choices, and aligning use cases with agent demand. This gives clear context for when to use the tool, but it does not explicitly mention when not to use it or name alternative tools as a direct contrast.

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