Verify Phone

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

Annotations already mark this as non-read-only and destructive, and the description adds no further behavioral context. It does not disclose whether the code is consumed, whether verification is irreversible, or what happens on failure, leaving the agent without important side-effect information.

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. Every word contributes to understanding the tool's core action.

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 verification tool the description covers the basic action, but it omits the expected relationship with startPhoneVerification and does not clarify that the required fields live inside a nested requestBody object. With no output schema, some information about the outcome would improve completeness.

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 100%, so the schema already documents the requestBody structure and the required phone and code fields. The description merely restates 'phone number' and 'code' without adding format, sequencing, or other semantic details beyond 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 uses a specific verb ('Confirm') and resource ('a phone number') with the code, making the tool's action unambiguous. It also clearly distinguishes verifyPhone from the sibling startPhoneVerification by focusing on the confirmation step.

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 'with the code that was sent' implies this is used after a verification code has been delivered, but it never explicitly states 'use after startPhoneVerification' or mentions any exclusions. The usage context is implied rather than directly instructed.

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