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

The description adds significant behavioral context beyond the annotations: the operator queue is currently unstaffed, the handoff will expire, callback_url fires on expiry, no secret is needed for an unregistered handle, and there is a rate limit of 5/min. These are exactly the kind of operational caveats an agent needs to decide whether and how to invoke the tool. The description aligns with annotations (not read-only, not idempotent, not destructive).

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 front-loaded with the key trigger condition and is compact. The first sentence establishes when to use it, and the second delivers the critical caveats in a NOTE. There is no filler; every clause contributes operational guidance.

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 tool with no output schema and seven parameters, the description covers the essential lifecycle: handoff_id to poll, expiry, callback behavior, auth requirements, and rate limiting. However, it doesn't spell out the exact return shape or how to poll, and the statement that callback_url 'fires on expiry' sits oddly against the schema's 'optional webhook on resolve' — a minor ambiguity that prevents a 5.

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?

With 86% schema description coverage, the schema already documents most parameters, so the baseline is 3. The description adds useful meaning for handle/secret ('no secret needed for an unregistered handle'), for callback_url (fires on expiry), and for the overall lifecycle (handoff_id, expires_at). It doesn't elaborate on url, task, or context, but those are already well described in the schema.

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 conveys the tool's purpose: when an agent is blocked by a human-only wall, it can 'park' the task and get a handoff_id to poll. It names the resource and the action, and the trigger examples (OAuth, CAPTCHA, email/SMS verify) make the use case vivid. It does not explicitly say 'create a handoff request', and it doesn't differentiate itself from sibling human_task_post or human_browse tools, so it loses a point.

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 gives concrete trigger conditions for use ('Stuck at a human-only wall') and lists examples of such walls. It also conveys practical constraints: the operator queue is not staffed today, the handoff expires, and there's a 5/min rate limit. It does not explicitly state when NOT to use this tool or name alternative tools, so it's clear but not exhaustive.

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