get_email_insights

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds real value beyond that: the report is 'computed when it was sent' (a frozen snapshot, not live), returns per-check results plus a score, and warns the score is not an inbox-placement probability — meaningful behavioral context.

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?

Two tight sentences, front-loaded with the core action and output, followed by the disambiguating caveat. Every clause earns its place with no filler.

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?

With no output schema, the description carries the return-value burden and does so adequately by naming per-check results and the 0-10 score and clarifying the score's meaning. It could say more about what individual checks contain, but it is sufficient for correct invocation.

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% and the single email_id parameter is fully documented (uuid, sourced from send_email). The description adds no syntax or format meaning beyond the schema, so the baseline 3 is appropriate.

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?

States a specific verb (Get) and resource (best-practice report for one email) with the exact output (per-check results and a 0-10 score). The disclaimer that it is 'NOT an inbox-placement probability' cleanly disambiguates it from the sibling get_deliverability, so an agent can route without opening schemas.

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?

Usage is only implied — it retrieves insights for one already-sent email. There is no explicit when-to-use statement or named alternative (e.g., when to prefer get_email vs get_deliverability), though the score clarification hints at its scope.

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