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

Annotations already mark this destructive/openWorld/non-idempotent, but the description adds critical context beyond them: the reply e-mails a real person, cannot be recalled, goes to exactly one recipient, and forbids cc/bulk/attachments. It also discloses the auth requirement, which annotations don't cover.

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 'WRITE:' and the irreversibility warning, then recipient rules, auth, sibling pointer, and API shape. Every sentence carries decision-relevant information with no filler.

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 one-shot write with no output schema, the description covers the safety profile, recipient semantics, auth requirements, and alternative tool. An agent has everything needed 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, but the description adds meaning beyond the schema by clarifying that `to` may name only ONE other single address (no cc, no bulk) and that the default is the ticket's customer looked up from the ticket.

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+resource with explicit scope: 'send a customer-visible reply on ONE ticket'. The 'WRITE' prefix and 'customer-visible' qualifier immediately distinguish it from the sibling zammad_add_internal_note.

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?

Explicitly routes the agent: use this for customer-visible replies, use zammad_add_internal_note for an internal remark. Also states the token prerequisite (agent token, customer token refused). 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.