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

Adds real context the annotations do not carry: the agent-token requirement (customer tokens are refused and why), the fact that the ticket's other data is untouched, and the exact endpoint/payload shape. One tension: annotations declare destructiveHint=true while the text says existing ticket data is unchanged — a mild mismatch about destructiveness, though both agree this is a write.

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-loads 'WRITE' and 'INTERNAL', then auth precondition, then side-effect, then endpoint. Every clause carries information; nothing is padding.

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 3-parameter write with no output schema and full annotation coverage, the description supplies the auth precondition, the visibility semantics, the non-mutation guarantee and the wire format. Nothing needed to call 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 100%, so ticket_id, body and subject are already documented with types and length bounds. The description only adds the 'ONE ticket' cardinality constraint and the note/public distinction, so baseline 3 is appropriate.

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 ('add an INTERNAL note ... to ONE ticket') with the key qualifier that distinguishes it from a customer reply. An agent can immediately tell this apart from zammad_reply_to_ticket without opening either schema.

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?

The description makes the use case unambiguous: visible to agents only, never e-mailed to the customer, which implicitly routes customer-facing messages to reply_to_ticket. It stops short of naming that sibling explicitly, so the exclusion is inferable rather than spelled out.

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