brewfather_preview_recipe_update

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It accurately discloses merge semantics (deep-merge for objects, replace for arrays), the normalization report (unit/color), and rejection conditions (string tags, unsupported misc units). It does not mention any side effects, authentication, or rate limits, but for a preview tool these are less critical. The behavior described is consistent with the tool's name and purpose.

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, front-loaded with the primary purpose, followed by essential behavioral details. Every sentence earns its place—no fluff, no repetition. The information is dense but organized logically: purpose, output, merge behavior, and error handling.

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 preview tool with two parameters, the description covers the key aspects: purpose, merge semantics, error conditions, and the need to fetch the recipe for arrays. It does not specify the exact structure of the preview report or what the 'confirmation' step entails, but that might be handled by the apply tool. Overall, it is adequate for an agent to correctly invoke the tool, with minor gaps around the exact response format.

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 covers only the 'changes' parameter (with a description about partial objects and complete arrays), while 'recipeId' has no description. The tool description compensates by elaborating on array replacement ('send a complete ingredient array') and rejection criteria, which adds beyond the schema. However, it still lacks a precise description of what 'changes' can contain beyond the schema's generic object definition. Overall, it adds meaningful context.

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 clearly states the verb (validate and preview), the resource (recipe update), and the key distinction of not writing. It explicitly sets it apart from apply_recipe_update, and the mention of 'preview' makes the dry-run nature obvious even without reading the sibling tools.

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 implies when to use this tool (when you want to validate changes before applying) and provides operational guidance for nested objects and arrays. It does not explicitly name alternatives like 'apply_recipe_update' or 'preview_recipe_create', but the context of 'without writing it' and the sibling list makes the intended usage clear. A slight deduction for not explicitly mentioning alternatives when they exist.

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