submit_pin

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

No annotations, so the description carries the behavioral burden. It discloses the two-step auth context (SMS code issued by login), which is useful. However, it says nothing about failure behavior, attempt limits/lockout, or whether the session becomes authenticated — meaningful gaps for an auth-credential submission tool.

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 zero waste; the trigger condition follows immediately. Nothing redundant.

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 need not be explained, and the trigger is clear. Still, for an auth-credential tool with no annotations, the description omits failure/lockout behavior and any post-submit state change.

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?

One parameter with 0% schema description coverage, so the schema adds no meaning. The description compensates partially by clarifying the value is an SMS-delivered PIN code, but gives no format, length, or digit constraints.

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 ('Submit SMS/PIN code') and ties it to the login handshake, making it clearly distinct from siblings like login/logout/session_status. It doesn't explicitly name an alternative tool, but the purpose is unambiguous.

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?

Gives an explicit trigger condition: use it only after login has returned pin_required. That is real when-to-use guidance for a second-factor step. It stops short of stating what to do if the PIN fails or how many attempts are allowed.

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