latest_otp

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

No annotations exist, so the description carries the full burden and does real work: it discloses the ~3 minute expiry window, the meaning of the redacted=true case, and an explicit anti-fabrication rule. It stops short of covering permissions, failure modes when no OTP exists, or freshness edge cases.

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?

Three short sentences, each earning its place: what it returns, how long it is valid, and what to do on redaction. The most actionable content (don't invent a code) lands last with no padding around it.

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?

An output schema exists, so return values needn't be explained, and the description covers the one output nuance an agent must act on (redacted digits). It leaves out what happens when no OTP is present or when the code has already expired, which are realistic call-time questions for a tool with a 3 minute validity window.

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?

Zero input parameters, so there is nothing for the description to disambiguate; the baseline applies. It does not need to compensate for any schema gap.

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+resource ('Newest OTP from the phone') and enumerates the source channels (SMS/bank/mail/WhatsApp notification), which cleanly separates it from siblings like last_whatsapp. An agent knows exactly what it gets without opening the schema.

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 implies the use case (fetch a code for a user waiting on one) but never states when to call it versus alternatives such as last_whatsapp, nor any preconditions. With no closely competing sibling, the gap is mild rather than harmful.

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