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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds real behavioral context beyond that: results are ordered most-recent-first, and the recipient count is a snapshot 'captured at send time' rather than live data — useful semantics for interpreting results.

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?

Two sentences, fully front-loaded: what is listed and how it is ordered comes first, the parameter constraint second. No filler or restatement of the title.

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 single-optional-parameter read-only list tool with no output schema, the description covers the essentials: scope, ordering, a key returned field's semantics, and the parameter's bounds and default. Nothing needed to invoke it correctly is missing.

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 must carry the parameter. It documents the sole parameter's range (1-50) and, critically, a default of 20 that appears nowhere in the schema, which the agent needs to reason about result size.

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 (List) and resource (announcements) plus scope ('this organization has sent'), with added detail on ordering and the recipient-count field. It does not explicitly name or contrast with the sibling announcements_manage, so differentiation is left to the query/manage naming convention.

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 'list announcements this organization has sent' — an agent can infer this is the read path for sent announcements. There is no explicit when-to-use statement, no exclusion, and no mention of the announcements_manage alternative for creating or sending.

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