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

Annotations already declare destructiveHint=true, idempotentHint=true, readOnlyHint=false, so the safety profile is covered. The description adds the useful auth context ('attachments:write scope'), but does not explain what 'destructive' means here (partial update vs. full replace, whether omitted fields are cleared, or whether related entity IDs are re-linked).

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, no filler, and the core action is front-loaded before the permission note. Nothing is wasted.

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 an 11-parameter, destructive, non-idempotent-flagged mutation with no output schema, the annotations cover safety but the description leaves gaps: partial-update semantics, field-clearing behavior, and sibling routing are all unstated. Adequate but with clear holes given the complexity.

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% with all 11 parameters documented in the schema itself, so the baseline is 3. The description adds nothing beyond the schema — it doesn't say which fields are actually updatable, whether the update is partial, or what the entity-linking params (work_order_id, pm_schedule_id, etc.) do when changed.

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 (attachment) plus the lookup key (by ID). It's clear what the tool does, but it offers no differentiation from the many sibling tools like get_attachment, delete_attachment, create_attachment, or the dozens of other update_* tools in the 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 only guidance is 'Requires attachments:write scope,' which is a permission prerequisite rather than when-to-use guidance. It never says when to prefer this over create_attachment/get_attachment/delete_attachment, nor what conditions warrant an update.

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