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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds valuable behavior beyond annotations: the feature dependency, the 404 error condition, and the non-obvious counting semantics for notification batches. This gives the agent useful expectations about the operation's behavior and edge cases without contradicting the annotations.

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 three sentences with no filler. It front-loads the core purpose, then adds the essential counting rule, and finally the feature prerequisite and error behavior. Every sentence contributes meaningful information that an agent needs to call the tool correctly.

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?

This is a simple tool with one optional parameter and no output schema. The description fully covers what count is returned, how it is calculated, the scope (current team), and a key failure mode (404 when Notification Center is not enabled). No critical information for correct invocation is missing, and the absence of an output schema does not create ambiguity because the return value is a count implied by the tool's name and description.

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 already covers the only parameter (team_id) with a detailed description including UUID format, fallback behavior, and OAuth guidance, so schema description coverage is 100%. The tool description adds context about 'current team' and counting semantics, but it does not add new parameter-level details beyond what the schema already provides. Baseline 3 is 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 states a specific verb ('get'), a specific resource ('unread notification count'), and a clear scope ('for the authenticated user's current team'). It also clarifies the counting unit ('Each notification batch with unread members counts as 1'), which distinguishes this count from a raw member-level or item-level count. This is more specific than the tool name alone and gives an agent a precise understanding of what is returned.

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 provides clear functional context: it targets the authenticated user's current team, and requires the Notification Center feature or it returns 404. This helps an agent decide when the tool is applicable. It does not explicitly name alternatives such as getNotificationCounts or listNotifications, but the usage context is clear enough that an agent can infer when this tool is the intended one.

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