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

Annotations already declare readOnlyHint=false, destructiveHint=true, and idempotentHint=true, so the mutation profile is covered structurally. The description adds genuinely new context by stating the required parts:write scope, but it never explains what makes the operation destructive, whether omitted fields are cleared or preserved (full replace vs partial update), or how to reconcile destructive with idempotent.

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 prerequisite. Every clause carries information.

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 destructive mutation with no output schema, the most decision-relevant facts are absent: whether the update is partial or full-replace, what happens to fields omitted from the call, and whether the change is reversible. The auth note is useful but does not compensate for missing mutation semantics.

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%, and all 13 fields carry their own descriptions (including type, range, and format constraints and the DEPRECATED note on supplier). The description adds nothing parameter-level, so 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?

States a specific verb and resource ("Update an existing part/inventory item") plus the identifier used to address it ("by ID"), which clearly distinguishes it from create_part, get_part, and delete_part. It stops short of explicitly naming those siblings or the scope of what is updatable.

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 no when-to-use guidance, no exclusions, and no routing to alternatives such as bulk_update for multiple parts. The only conditional content is the permission prerequisite, which is auth rather than usage selection.

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