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

Annotations declare readOnlyHint=true and openWorldHint=true, so the description doesn't need to discuss side effects. It adds contextual value by noting the plan requirement for bulk lookups and listing the fields available, but it doesn't disclose specifics like rate limits, error handling, or whether there's a maximum number of IPs beyond the schema's min/max length on the string. This is adequate given annotations cover the read-only nature.

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 a single paragraph of moderate length, hitting key points: what it does, examples of data returned, use cases, and the plan requirement. It is front-loaded with the action and resource. It could be slightly more concise, but every sentence adds value.

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 has 5 parameters and no output schema, but the description compensates by listing the default and optional fields, clarifying the 'include' behavior, and noting the plan prerequisite. It doesn't detail response format or error cases, but for a read-only bulk lookup, the description covers the essentials. A minor gap is the lack of a note that 'include_optional' overrides 'include' in the description, though the schema covers it.

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 100%, so all parameters are documented. The description adds value by explaining the purpose of the 'include' parameter (optional fields for additional context) but doesn't go beyond the schema for parameters like 'model' or 'verbose'. Since the schema already covers parameter meanings, a baseline score of 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 clearly states the tool performs bulk IP geolocation and security lookups for multiple addresses, enumerating the types of data returned. It distinguishes itself from siblings by focusing on bulk versus single lookups, and the 'bulk' in the name is reinforced by the description's emphasis on lists.

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 description provides clear use cases ('analyzing lists of IPs, grouping by country/region, flagging suspicious origins') and notes the plan requirement, which is essential. However, it doesn't explicitly contrast with single-lookup siblings (ipstack_lookup, ipstack_check) or state when to prefer one over the other, leaving that inference to the agent.

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