get_email_analytics

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

Annotations include readOnlyHint: true, and the description adds significant context: 'Reads from the local index (auto-refreshed if stale or empty), not live IMAP — reflects the last sync.' This explains data source and staleness, going beyond the annotation to clarify behavioral nuances. No contradiction.

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 concise (five sentences) and front-loaded with the core purpose. Each sentence adds value: output definition, use cases, alternatives, and data source/behavior. No fluff or repetition.

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?

The tool has moderate complexity with 2 parameters (both documented), no output schema, and clear output description (top senders, busiest hours, volume by folder). The description explains what it returns and its data source, making it fairly complete. Minor gap: it does not specify sampling behavior details or formatting, but that is not critical for an analytics summary tool.

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?

Schema coverage is 100%—both 'days' and 'limit' have descriptions in the schema. The description does not explicitly explain these parameters, but since the schema already provides meaning, a baseline score of 3 is appropriate. No additional semantic value is added beyond schema.

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 function: 'Generate sampled mailbox analytics including top senders, busiest hours of day, and volume breakdown by folder.' It specifies the resource (mailbox analytics) and the exact outputs, and distinguishes from sibling tools by naming alternatives (get_email_stats, get_volume_trends).

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?

Explicit usage guidance is provided: 'Use for productivity insights and communication pattern analysis' and directs away from alternatives: 'Prefer get_email_stats for a fast aggregate count summary. Prefer get_volume_trends for per-day message volume history.' This clearly tells when to use this tool versus siblings.

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