update_registry_item

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

Annotations already declare destructiveHint=true and idempotentHint=true, so the mutation profile is known. The description usefully adds the semantics behind 'destructive' — that this is a full replace where omitted fields are wiped — which is real added context. It says nothing about permissions, return values, or partial-update alternatives.

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?

A single sentence with the replace constraint front-loaded and zero filler. Nothing could be removed without losing 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?

The full-replace clarification is essential and present, and the output schema is absent so nothing is owed there. But for a 7-parameter destructive mutation with 29% schema coverage, the description leaves five parameters and the auth/permission requirements entirely unexplained.

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 coverage is only 29% (2 of 7 params documented), so the description must compensate and does not. It correctly conveys that all 7 parameters are required, but adds no meaning for quantity, group_gift, marked_fulfilled, personal_note, or most_wanted — notably personal_note, whose semantics are not self-evident.

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 registry item') and distinguishes itself implicitly from the add_registry_item / remove_registry_item siblings by naming the existing-item scope. Clear, though it never explicitly contrasts itself with those siblings.

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?

Warns that 'all fields must be supplied (it's a full replace)', which is a genuine precondition for calling it correctly. However, it gives no guidance on when to prefer this over add/remove, and no mention that collection_item_id comes from get_registry (that hint lives only in the schema).

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