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

With no annotations the description carries the full burden, and it does well: it declares the action irreversible, discloses two side effects (in-app notice plus a real email when alsoEmail is true), and explains the confirm-gated preview path. It omits permission/authorization requirements and any rate or volume limits.

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, front-loaded with purpose and scope, then risk, then the required workflow. No filler; each sentence contributes either routing or safety information.

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 7-parameter irreversible mutation tool with no annotations and no output schema, the description covers irreversibility, side effects, audience semantics, and the confirmation flow, which is most of what an agent needs. It stops short of stating who may send or what the preview response contains.

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 only 29% (confirm and locationId documented), so the description must compensate. It adds meaning for audience (coaches/clients/ALL), alsoEmail (triggers a real email), and confirm, but leaves title, body, and organizationId entirely unexplained.

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 (Send) plus resource (announcement) and the exact audience scope (coaches, clients, or everyone), which cleanly separates it from the individual-message sibling send_message_to_client and the read-side list_organization_announcements.

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?

Explains the gated workflow – show the exact text and audience first, and the confirm flag controls preview vs execution – so an agent knows the required sequence, but it never names an alternative tool or an explicit 'do not use when' condition.

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