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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds the default window (24 hours), which is useful context, but leaves open whether 'customer messages' means inbound only, whether results are capped, and whether it's 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?

A single compact sentence with the two returned entity types and the window front-loaded. Nothing is wasted, though the phrasing 'new customer messages' is slightly ambiguous and could be tightened.

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 a one-optional-parameter read tool with no output schema, the definition covers the essentials but never hints at the shape of the response (counts? lists? per-customer grouping?), which matters because there is no output schema to fall back on.

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 0%, so the description does carry the meaningful part: the single parameter is a lookback window in hours with a default of 24. However, it never states the 168-hour (7 day) upper bound enforced by the schema, nor the 1-hour minimum, so it only partially compensates.

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 names the two resources returned (new customer messages and new customers) and the time window, so the agent knows this is a 'catch-up' summary tool rather than a search tool. It lacks an explicit verb and does not name the sibling it differs from (e.g. find_customer or office_summary), so it falls short of a 5.

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?

There is no when-to-use or when-not-to-use guidance beyond what the name implies. The agent must infer that this is for returning after an absence and that find_customer/find_estimates exist for targeted lookups; the description says nothing about that routing decision.

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