lookup_user

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

With no annotations provided, the description carries the full burden and does add useful behavioral context: it supports partial/informal name matching and accepts multiple query types including username and department. However, it does not disclose edge-case behavior such as no-match handling, ambiguity handling, or access permissions.

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 front-loads the core purpose in the first sentence, then gives usage context and compact parameter definitions. Every sentence contributes useful information with no filler or 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?

For a low-complexity lookup tool with an output schema, the description covers purpose, usage context, return fields, and both parameters. It is nearly complete, but slightly lacks explicit guidance on what happens with no matches or ambiguous partial matches.

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 description coverage is 0%, but the description fully compensates by explaining both parameters: query accepts a name fragment, username, email, or department, and limit sets maximum matches within a 1-20 range. This adds the semantic meaning missing from the bare schema types.

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 a specific verb and resource: 'Look up a person' and names the exact fields returned (name, email, department, manager, VIP status). This clearly distinguishes it from all listed incident- and CMDB-focused sibling tools.

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?

It explicitly describes when to use the tool: resolving partial or informal names into the exact values incident tools require, and checking VIP status before deciding urgency. It does not name excluded alternatives, but no sibling tool offers user lookup, so the guidance is sufficient.

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