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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuinely non-derivable behavior: message bodies are redacted unless the caller is creator or assignee, and the call does not spend points. Ordering ('recent') is mentioned but not defined as ascending or descending.

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?

Three short sentences, each carrying distinct information: scope, access-control caveat, and cost. Nothing is repeated from structured fields and the most important sentence (scope) is front-loaded.

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 simple read-only inbox tool with one optional parameter and no output schema, the description covers scope, redaction rules, and cost. Only minor gaps remain, such as result ordering, approximate event types, and whether the inbox is bounded by a time window.

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?

There is one optional parameter, 'limit', at 0% schema description coverage, although the schema does supply a default of 30 and bounds of 1-50. The description never mentions the limit, so its meaning and the effect of exceeding the cap (if any) are left entirely to the schema's numeric constraints.

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 resource and scope: recent events on tasks the caller created, is assigned to, or applied to. That is far more informative than the bare name 'list_inbox'. It does not, however, distinguish itself from the sibling get_task_history, which plausibly returns overlapping data, so it stops 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?

Usage is implied by the scope sentence (check recent activity across your tasks) but there is no explicit when-to-use, when-not-to-use, or named alternative such as get_task_history or find_tasks. The agent must infer the choice from the scope wording alone.

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