Add item

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

The description goes beyond the annotations by disclosing that 'Adding something already on the shelf just updates its category,' revealing an upsert/merge behavior rather than a simple create or error. This is valuable context that annotations do not provide. No contradiction with 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?

The description is three sentences long, front-loaded with the main purpose, and every sentence conveys essential information: what it does, when to call it, and its update behavior. There is no unnecessary verbosity.

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 simple mutation tool with two fully documented parameters, an output schema, and annotations declaring it non-read-only and non-destructive, the description is sufficiently complete. It covers purpose, usage trigger, and the key behavioral nuance (updating existing items) without requiring additional detail.

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 detailed descriptions for both name and category. The description's mention of 'bottle, mixer, or garnish' loosely maps to the category parameter but does not add meaningful semantics beyond the schema. Baseline 3 is appropriate.

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 opens with a specific action: 'Add one bottle, mixer, or garnish to the bar.' It further clarifies scope with 'once per item' and notes the update behavior for existing items, clearly distinguishing it from sibling remove_item and list_inventory.

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?

It explicitly states when to call: 'Call this when the user buys or acquires something, once per item.' This is a clear, actionable trigger. It does not explicitly name alternatives or exclusions, but the sibling tool names provide sufficient context for when not to use it.

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