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

The description adds no behavioral detail beyond the action name. The annotations indicate destructiveHint=true and readOnlyHint=false, so the agent knows this is a mutating operation, but the description does not explain what state changes occur, whether the action is reversible, or what side effects starting a session may have. It does not contradict the annotations but also does not enrich 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 a single front-loaded sentence with no filler, which is good. However, it is overly terse and omits important operational context, so the brevity comes at the cost of usefulness. It earns its place but does not carry enough information.

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 destructive, state-changing tool with no output schema and fully undocumented parameters, this description is incomplete. An agent cannot determine what happens when the session starts, what the return value is, or how to use the idempotency fields. The annotations help with the safety profile, but the overall context is insufficient for correct invocation.

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%, so the description must compensate. It loosely maps to interview_session_id ('interview session') and interviewer_user_id ('explicit interviewer'), but it does not explain the idempotency_key, request_id, or the relationship between the required parameters. The optional idempotency-related fields remain entirely undocumented.

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: 'Start an interview session' for an 'explicit interviewer.' It conveys the core action and distinguishes this tool from siblings like cancel, complete, or read. However, the phrase 'explicit interviewer' is somewhat vague and would benefit from clarifying why the interviewer must be specified.

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?

No guidance is given about when to use this tool versus alternatives. It does not mention prerequisites like session readiness, whether the session must already be scheduled, or what conditions make 'start' appropriate. The description also does not exclude cases where a sibling like interview_sessions_complete or interview_sessions_cancel would be more suitable.

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