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

Annotations already declare readOnlyHint=false, destructiveHint=true, openWorldHint=true, but the description adds critical context beyond them: a real e-mail reaches a real person, timing follows the Flow Sequence/template_id, and the action cannot be recalled from this server. That irreversibility detail is exactly what an agent needs before calling a destructive tool.

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?

Front-loaded with the highest-stakes fact (write that sends a message to a real customer) and structured as escalating constraints. Slightly verbose with the caps-heavy warning framing, but every sentence carries operational weight.

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 destructive, non-idempotent mutation with no output schema, the description covers safety profile, timing, reversibility, and the confirmation gate. An agent has everything required to invoke it correctly.

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 coverage is 100%, so the baseline is 3; the description goes further by emphasizing the confirm_send_email: true requirement and the template_id override semantics as behavioral guidance rather than mere field docs. It does not, however, add format examples beyond the schema.

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 and resource ('queues ONE company review invitation e-mail') with explicit scope ('ONE', 'company' vs product invitations) and names the endpoint. An agent can distinguish it from sibling list/tag tools immediately.

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?

Explicit when-to-use ('Only call it when the user has explicitly asked to invite this exact customer'), the required confirm_send_email: true gate, and an explicit absence of alternatives ('There is no bulk or SMS invitation tool'). Nothing is left to inference.

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