List CFR parts in the local index

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is fully covered. The description adds that results come specifically from the 'local index' and what fields are returned, but the return fields are already in the output schema, so the incremental behavioral disclosure is modest.

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 tight sentences: the first states scope and return content, the second states the use case. Front-loaded and free of filler.

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?

With a rich output schema and complete annotations, the description covers purpose, scope, and use case, leaving little for an agent to guess. Only minor details (ordering, whether the index can be stale/incomplete) are unstated.

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?

There are zero parameters, so the baseline is 4; nothing about parameter meaning needs documenting and the schema fully covers the (empty) input.

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 ('Enumerate') and resource ('Title 38 CFR part') scoped to the local index, and states the returned fields (structure-tree title, section/appendix counts). It is clear on its own, but it never names or contrasts with siblings like browse_title38 or search_regulations, which could plausibly overlap.

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?

'Use this to discover which parts are searchable' gives a concrete when-to-use condition tied to a downstream action. It stops short of stating when-not-to-use or pointing to an alternative sibling for related tasks, so it is clear context without exclusions.

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