Get Lookup Values

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

With no annotations, the description carries the full burden for safety disclosure. It explicitly states 'Lookups are read-only via the API,' clearly conveying that this tool has no side effects. This adds behavioral context beyond the parameter schema.

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 two sentences, front-loaded with the primary function, and includes usage context and a read-only note without any wasted words.

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 read-only tool with a single required enum parameter and an optional limit parameter, the description covers the purpose, usage context, and safety profile. It doesn't describe the return structure, but 'valid values' implies a list, and the schema fully documents parameters.

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?

Both parameters are already documented in the schema with descriptions and an exhaustive enum for lookup_name, so the description adds little additional semantics. The tool description gives examples of lookup names, but these are already enumerable in the schema. Baseline 3 is appropriate given 100% schema coverage.

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 'Get' with a clear resource 'valid values for an HR Partner lookup list' and lists concrete examples, distinguishing it from sibling entity-specific tools. The phrase 'discover valid filter values for the other tools' further clarifies its role.

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 explicitly instructs to use this tool for discovering valid filter values for other tools, which is clear usage guidance. It does not mention when not to use or alternatives, but no sibling tool provides lookup values, so the guidance is adequate.

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