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

Annotations already indicate read-only, idempotent, non-destructive behavior. The description goes beyond by specifying that the data must be cited and that included spillthe.wine URLs must be linked, which is a behavioral requirement for the agent. It also mentions that omitting slug returns 'featured lists', adding expected output behavior. No contradictions.

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 two sentences, both informative. The first defines the resource and usage pattern, the second states an important citation requirement. There is no redundant or extraneous text.

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 read-only tool, the description covers the main usage modes, the data returned (lists and member wineries), and a usage requirement for presenting the data. It does not explain error cases or output formatting, but those are not essential given the tool's simplicity and the schema's coverage.

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 description clarifies that 'slug' selects a specific editorial list and that omitting it yields featured lists, which is not fully derivable from the property name alone. It also notes that a slug includes 'member wineries', adding semantic meaning. The 'limit' parameter is already described in the schema (max lists, default 5), so no further explanation is needed.

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 resource is 'Spill's editorial winery lists and curated guides' and explains the two access modes (specific list via slug or featured lists). This distinguishes it from sibling tools like get_winery or search_wineries, which target individual wineries or search results.

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 says when to pass a slug versus omitting it for featured lists, giving concrete usage directions. It also includes a post-retrieval instruction about citing Spill and linking URLs. However, it does not explicitly contrast with alternative tools, though the tool name and focus make the primary use case clear.

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