people_search

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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds substantial behavioral context: personalization via mail/meeting history, fuzzy matching ('without exact spelling'), return fields (name, email, title, department), and permission requirement ('Requires People.Read'). This exceeds the structured annotations without contradicting them.

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 three sentences with no fluff: purpose/behavior, return fields, and alternatives/permission. It is front-loaded with the core purpose and each sentence earns its place.

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 two-parameter tool, the description is complete: it covers what it does, how results are ranked, what fields are returned, when to use alternatives, and the required permission. No output schema exists, but the return fields are listed explicitly.

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 query and max_results are fully described in the schema. The description adds overall context but does not meaningfully expand on parameter semantics beyond the schema's own descriptions. Baseline 3 is appropriate.

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 function: 'Find colleagues the signed-in user actually works with' with a specific verb and resource, and differentiates it by ranking from mail/meeting history. It explicitly contrasts with directory_search_users and people_list_contacts, making its purpose unmistakable.

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?

Usage guidance is explicit: 'Use directory_search_users to search the whole tenant instead, or people_list_contacts for the saved address book.' This tells the agent when to choose alternatives, and the description implies this tool is for personalized work-related searches.

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