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

With no annotations provided, the description carries the full behavioral burden and does so well: it discloses defaults (7 days, up to 92), timezone cutover at local midnight, units in seconds, available comparison behavior, and the absence of per-agent/per-hour breakdowns. It omits permission/auth requirements and rate-limit behavior, which keeps it from a 5.

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 front-loaded with a clear purpose statement and then organized into action-specific bullet points, which makes it easy to scan. It is somewhat long, but nearly every sentence adds operational detail; minor trimming could improve it.

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?

For an 11-parameter tool with no output schema and no annotations, the description is substantial: it outlines what statistics returns and what export supports. It does not cover device/auth context or response shape for export, but the schema handles most remaining parameter-level detail.

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 the baseline is 3; the description adds meaningful semantics on top, including date defaults, the 92-day statistics cap, midnight timezone handling, seconds as units, and how compareFromDate/compareToDate work. It leaves device and status semantics primarily to the schema, so it is not a full 5.

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 that the tool reports and exports WhatsApp chat data, and it enumerates the two supported actions (statistics and export) with concrete details. It does not, however, distinguish itself from sibling tools such as get_whatsapp_chat_statistics or export_whatsapp_chats, which appear to overlap directly.

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 explicit use cases ('weekly reports, response time reviews, backups, and feeding chat lists into another system'), which helps an agent decide when to reach for it. It stops short of naming when not to use it or pointing to the sibling alternatives that likely handle statistics or export separately.

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