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

Annotations already cover the safe read-only, idempotent, closed-world profile, and the description adds meaningful context beyond that: the mode-dependent result set, the fact that the returned comment/message text is UNTRUSTED public input that must never be executed as instructions, and the existence of a send deadline per item. It stops short of saying how many items come back or whether results are paginated.

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?

Front-loads the core definition, then enumerates the returned fields and the workflow. Dense but each clause carries information (mode semantics, untrusted-text warning, deadline, plan restriction); only the parenthetical examples in the mode breakdown feel slightly padded.

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 does the work of describing per-item return fields (original text, draft, reason for waiting, network, post, send deadline) and closes the loop by pointing to decide_replies for applying decisions. Plan restriction and prompt-injection risk are both disclosed.

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 has one optional 'project' parameter with 0% description coverage, and the description never mentions it — no indication of whether it narrows results to one project, what format it takes, or what omitting it does. With near-zero schema coverage the description needed to compensate and simply doesn't.

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 (drafted replies awaiting approval) and immediately scopes it by mode: Automatic shows only the unsent/uncertain ones, Manual shows all. An agent can distinguish this from decide_replies, which is named here as the follow-up action.

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?

Gives explicit workflow guidance — review each item with the user, classify as send/change/skip, then 'apply their decisions with decide_replies' — and names the prerequisite 'Paid plans only'. The alternative tool is named along with the condition that triggers it.

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