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

Beyond the lone destructiveHint annotation, the description discloses that this is a partial update (unpassed fields are left alone), that changes are reversible by updating again, that the hidden deleted/spam status is not settable, and the underlying PUT endpoint. It does not cover permission/auth requirements or what the response contains, but it adds real behavioral context.

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 compact sentences with the field list and partial-update rule front-loaded; nothing is padding. The trailing 'Deskpro: PUT /api/v2/tickets/{id}' is mildly redundant for an agent but cheap.

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 10-parameter mutation tool with full schema coverage and no output schema, the description supplies the key non-schema facts: partial-update behavior, reversibility, and the unsettable hidden status. Missing only auth/permission notes and error behavior.

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 all ten parameters (including patterns, ranges and the status sub-status format) are already fully documented. The description only restates the field list and the hidden-status restriction, adding no syntax or format meaning beyond the schema — the baseline 3 applies.

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?

Opens with a specific verb ('Change') plus resource ('a ticket's') and enumerates the full set of mutable fields (subject, status, assignment, department, organization, urgency, hold, labels). This clearly separates it from deskpro_create_ticket, deskpro_get_ticket and deskpro_add_ticket_message without needing the 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?

It states partial-update semantics ('Only the fields you pass are sent') and one exclusion ('Cannot set the hidden (deleted/spam) status'), which are useful invocation rules. However there is no explicit when-to-use guidance relative to sibling write tools or prerequisites (e.g. resolving vs adding a reply).

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