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

Annotations already declare this a safe, read-only, idempotent, non-open-world call, so the safety profile is covered. The description adds that the content is a fixed five-step protocol (static reference material), which is modestly useful, but it discloses nothing about format, length, or how the steps should be applied.

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?

A single front-loaded sentence with no filler; the verb and resource lead and the applicable scope trails. Nothing is wasted.

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?

With zero parameters and an output schema present, the description need not explain return values, and it correctly identifies what will be returned. Adequate, though the title/description mismatch ('Three Words Check' vs 'five-step protocol') could mislead about what the payload contains.

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?

The tool takes zero parameters, so the baseline of 4 applies; there is nothing for the description to disambiguate. No parameter-related value is expected or missing.

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?

States a specific verb ('Return') and resource ('Trust Onion's five-step family verification protocol'), scoped to suspicious calls, texts, and video calls. It is distinguishable from siblings like list_scam_types and assess_call_scenario, though it never explicitly contrasts itself with them. Minor confusion: the title promises 'the Three Words Check' while the description describes a five-step protocol.

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 phrase 'for suspicious calls, texts, and video calls' hints at the domain, but there is no explicit when-to-use instruction and no routing against siblings such as assess_call_scenario or explain_scam_type. An agent must infer the trigger condition on its own.

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