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

Annotations already establish that this is a write operation (readOnlyHint=false) in an open world. The description adds useful context: the editToken authorization requirement and where it comes from. That said, it does not address what happens on a duplicate item, a missing board, or an invalid token, so it adds context without adding depth.

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 sentences, zero filler, with the prerequisite front-loaded after the core action. The brevity is appropriate for the format, though the second sentence packs in a reference to "create", which is ambiguous about which sibling it means.

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 tool is a nine-parameter mutation with low schema coverage and no output schema. The description omits the meaning of the item-identifier parameters and what the call returns, which is too large a gap for an agent to write a correct call from.

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?

The schema has 22% description coverage, with nine parameters including optional fields like url, asin, emoji, title, catalogId and searchKeywords that the description never mentions. The description explains only editToken, leaving an agent unable to tell which identifiers are alternative ways to describe the item or which fields are optional. It does not compensate for the low coverage.

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?

The description names a specific verb and resource: adding an item to a wedding gift board. It is clear what the tool does, but it does not differentiate itself from the nearby sibling create_and_fill, which might also populate a board with items.

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 phrase "Requires editToken from create" gives a concrete prerequisite and implies the board must already exist, but the description never says when to use add_item instead of create_and_fill or create_wishlist. An agent must infer the choice from sibling names.

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