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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent call, so the safety bar is partly covered. The description adds genuinely new behavior: a human reads every message, there is no automatic reply, and the consent requirement for reply_email. Rate limits, expected latency, and what happens to an existing robot_key are not covered.

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 with zero filler; the purpose and the human-review expectation are front-loaded, and the conditional reply_email rule trails appropriately.

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 and full schema coverage, the description needs only to convey expectations and consent policy, which it does. It leaves unexplained what the agent receives back (a robot_key on first call) even though the schema hints at it.

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 description coverage is 100%, so all four parameters (including the type enum and message length cap) are already documented in the schema. The description's only added parameter context — reply_email requires the user's consent — duplicates the schema's own wording. Baseline 3 applies.

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 and resource ('Tell the convert.express team about a bug, a missing feature, or a question') and enumerates the exact categories covered. It is clearly distinguishable from every sibling tool (transcription, upload, job management) without opening any schema.

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 makes the triggering conditions clear via the enumeration of message types and adds a conditional rule ('Include reply_email only if your user wants an answer'). It does not state when not to use the tool or point to any alternative channel, so it falls short of a full 5.

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