Reference codes

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false. The description adds the valuable detail 'No network call', which is a behavioral trait not captured by annotations, and lists the content domains. It does not describe return format, but the presence of an output schema mitigates that need.

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 a single sentence that is front-loaded with the primary purpose ('Code tables used across tools') followed by a concise enumeration of content areas and the key behavioral note about no network call. Every element earns its place with no redundancy.

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 that there are no parameters, an output schema exists, and annotations cover safety and idempotency, the description is complete enough. It specifies what code tables are included and that no network call is made, which is sufficient for an agent to understand when and how to invoke 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?

There are zero parameters, so schema coverage is trivially 100%. With no parameters to explain, the description adds no parameter-specific semantics, but it also doesn't need to. The baseline for 0 parameters is 4, and the description appropriately focuses on content rather than parameters.

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 clearly states the tool's purpose: it provides code tables used across tools, listing specific categories like disclosure types, member types, and financial field names. This is a specific verb-less but informative description that distinguishes it from sibling data-retrieval tools, which all focus on specific entities or operations.

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 (reference/code lookup) but does not explicitly state when to use it vs alternatives, nor does it mention any exclusions. It says 'used across tools', which suggests it's a support resource, but there's no direct guidance on when an agent should call it.

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