Browse the PSA OpenSTAT catalog

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, covering safety traits. The description adds valuable behavioral context beyond annotations by emphasizing that the tool traverses the catalog 'one level at a time', implying the need for repeated calls to go deeper. This is a non-obvious behavior not captured in the annotations and is clearly disclosed. No contradiction exists.

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 extremely concise: two short sentences, each earning its place. The first sentence states the core functionality, and the second provides essential context about the catalog's scale and navigation strategy. There is no redundant or filler 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?

Given the simple single-parameter interface, the rich parameter description in the schema, and the presence of annotations and an output schema, the description is complete. It addresses the tool's purpose, behavior, and usage context without needing to explain return values (handled by the output schema) or safe-read characteristics (handled by annotations). An agent can correctly decide when to invoke this tool and how to use 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?

The input schema already provides 100% coverage with a detailed description of the 'path' parameter, including examples and the behavior of null/empty values. Therefore, the description does not need to elaborate further. It adds only incidental context about the catalog size (2,900 tables, 27 subjects) which helps understand the purpose of the path parameter but does not directly explain its syntax or semantics beyond the schema.

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 states 'List one level of the PSA OpenSTAT statistical catalog' with a specific verb and resource. It clearly differentiates from sibling tools like describe_psa_dataset and query_psa_dataset by focusing on catalog navigation rather than dataset details or querying. The additional context about walking the tree one level at a time makes the purpose 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 explains when to use the tool: 'so an agent can find a dataset without guessing a table id'. This provides clear contextual guidance for discovery use cases. However, it does not explicitly name alternatives or state when not to use it, such as mentioning that describe_psa_dataset should be used once a dataset ID is known. Without exclusions or explicit alternative references, it falls short of a 5.

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