List Namespaces

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

Annotations already declare read-only/idempotent/safe, and the description adds behavioral context by specifying the return format (array of namespace paths and comments) and the optional parent parameter's role in listing child namespaces. 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 brief and well-structured: a one-sentence purpose, a concise args list, and a returns line. No redundant or extraneous content.

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 two-parameter listing tool, the description covers purpose, parameters, and return format. It lacks details on edge cases like errors or empty results, but these are not critical given the annotations and simplicity.

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 fully describes both parameters (store, parent). The description adds marginal value by clarifying that parent is used to list children of a namespace, supplementing the schema's 'Parent namespace path'.

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 resource ('backup namespaces in a datastore'), clearly distinguishing it from sibling list tools like pbs_list_datastores and pbs_list_snapshots. The scope is precise and unambiguous.

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 implies its use case through its title and content, but does not provide explicit guidance on when to use it versus alternatives, such as when enumerating namespaces before listing snapshots. No exclusions are mentioned.

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