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

Annotations already mark the tool as read-only, but the description goes well beyond that: it discloses that the result respects the current admin's rights, root entities return full scalar fields, nested entities are stubs with expandable=true, and expansion requires re-calling with 'path'.

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?

Two sentences deliver the core purpose, syntax example, permission sensitivity, return behavior, and expansion workflow. Every sentence carries necessary information, and the key concept is front-loaded.

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 two-parameter introspection tool with read-only annotations and no output schema, the description adequately covers what the tool returns, how nested expansion works, and how it respects permissions. No critical behavioral gap remains.

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 both parameters are already documented. The description adds meaningful context, particularly explaining how 'path' relates to re-calling for nested expansion and reinforcing the syntax style. This goes slightly beyond the schema's literal property descriptions.

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 names a specific resource ('the operation's 'fields' selector') and states the exact behavior: returning the supported field set with GraphQL-like syntax. It is clearly distinguishable from sibling tools like get_operation_schema or get_extended_filter_schema because it focuses exclusively on the 'fields' selector and its expansion mechanics.

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 when this tool is relevant—when a caller needs the exact fields for an operation's selector and wants to expand nested entities—but it never explicitly names alternatives or states when not to use this tool. The contrast with siblings is not articulated, so the agent must infer routing from the narrow wording.

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