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

With only destructiveHint=true and a title in the annotations, the description carries most of the behavioral burden and does well: it discloses that Deskpro will auto-create the person when the email is new and that helpdesk triggers may send an email to the requester. Those side effects are not derivable from the schema or annotations.

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 the action and requester semantics; the trailing 'Deskpro: POST /api/v2/tickets.' is mildly redundant but costs little. 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 13-parameter creation tool with no output schema, the description covers the essentials: it says it returns the created ticket, explains requester resolution, and warns about the email side effect. It does not mention authorization requirements or how assignment fields interact, but the schema handles those fields well.

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 the baseline is 3, but the description adds real semantic value by explaining the person_id/person_email interplay and the resulting person-creation behavior, which the schema only gestures at with 'used when person_id is not given'.

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 ('Open a new ticket for a requester ... with a first message'), which cleanly distinguishes it from deskpro_add_ticket_message (adds a message to an existing ticket) and deskpro_update_ticket. The requester-identification parenthetical further pins down what kind of creation this is.

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 gives useful conditional guidance on how to identify the requester (person id vs. email), but never says when to use this tool versus sibling alternatives such as deskpro_add_ticket_message or deskpro_update_ticket, nor any prerequisites. Usage is implied by the verb, not stated.

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