vpc_list_instance_networks

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

The description discloses that identifier resolution accepts instance label, hostname, or ID, which is a behavioral trait not evident from the schema. It also states that the result is a combined list of both VPC types. With no annotations provided, this adds meaningful behavioral context beyond the function name.

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 short and uses clear labels (Args, Returns), but it duplicates information: the Returns line repeats the opening sentence, and the Args line repeats the smart-identifier sentence. While not verbose, the redundancy means not every sentence adds new 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?

For a one-parameter read-only list operation, the description provides everything an agent needs: the scope, accepted identifier formats, and the return composition. The output schema supplies the structured return shape, so no additional detail is required.

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 input schema defines instance_identifier as a string with no description, so the description carries the full burden of explaining the parameter. It explicitly lists acceptable formats (label, hostname, or ID) and names the parameter. This fully compensates for the 0% schema description 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 uses a specific verb ('List') and identifies the exact resource: VPCs and VPC 2.0 networks attached to an instance. This clearly distinguishes the tool from siblings like vpc_list_by_region and vpc_get_network_info. The mention of 'attached to an instance' removes ambiguity about scope.

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 does not explicitly state when this tool should be preferred over alternatives such as vpc_list_by_region. However, the resource-scoped purpose ('attached to an instance') implies the usage context. There is no explicit exclusion or alternative guidance, so the score is 3.

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