View the audit log

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

Beyond the readOnlyHint/destructiveHint=false annotations, it discloses the logged fields, ordering (newest first), success/failure status, and a genuine privacy constraint ("never email bodies"). It leaves retention depth and log completeness unstated, which matters for an audit tool.

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?

Three compact sentences, front-loaded with what is returned before the use case, and the parenthetical field list is dense but non-redundant. Nothing could be cut without losing information.

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 well by naming the fields per entry, plus ordering and privacy scope. The one gap is how far back the log extends, which an agent asking about older changes would want to know.

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 each parameter carries its own description, so the schema does the heavy lifting. The description adds only an implicit sense of the filterable universe ("every tool call", "account") without elaborating on tool/account/limit syntax, making the baseline 3 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?

The description opens with a specific verb and resource ("Show what this mail server has done: every tool call") and immediately enumerates what each entry contains. No sibling tool covers audit/history, and the description makes that scope unmistakable.

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?

It gives an explicit use case ("Use it to answer 'what did you change / send / draft?'"), which routes an agent to it for change-tracing questions. It does not name a competing tool or state when not to use it, but no sibling plausibly competes for this purpose.

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