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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=true, so the mutation and idempotency profile is covered. The description adds the write-scope requirement, which is genuine extra context, but says nothing about why the operation is flagged destructive or what state it can affect, so it does not go far beyond the 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?

Two short sentences with no filler; the action and target are front-loaded ahead of the scope prerequisite. Every clause carries information an agent can act on.

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 four-parameter, non-nested mutation with no output schema and rich annotations, this is close to adequate. The gaps are omission of partial-update semantics (all fields except id are optional, so unchanged fields presumably persist) and any hint of what the destructiveHint implies, which an agent updating a category would benefit from knowing.

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 four parameters (id, name, module, description) are already documented in the schema, including the module enum's workspace semantics. The description only restates that the target is addressed 'by ID' and adds no partial-update or field-level meaning beyond the schema, so the baseline of 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?

States a specific verb ('Update') and resource ('an existing work category') plus the identifier used ('by ID'), so the agent can distinguish it from create_work_category, delete_work_category, and list_work_categories. However it does not explicitly name or contrast those siblings, leaving differentiation to inference from the naming convention shared across the whole update_* family.

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 supplies one real prerequisite — 'Requires work_categories:write scope' — which tells the agent a permission is needed before calling. It gives no guidance on when to prefer this over alternatives, nor any exclusions, so usage is only implied.

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