finish_session

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

With no annotations provided, the description carries the full burden. It successfully discloses that the tool opens an external browser (significant side effect), but fails to clarify session lifecycle implications suggested by the name 'finish_session'—specifically whether the session terminates, cart clears, or if this action is reversible.

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, efficiently structured sentence delivers all necessary information without redundancy. The action ('Opens the browser') is front-loaded, followed by location ('checkout page') and purpose ('select a delivery time and pay').

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?

Given the tool's simplicity (zero parameters, no output schema) and the lack of annotations, the description provides adequate context for invocation. It explains the user-facing outcome (browser navigation to checkout) sufficiently for an agent to select this tool appropriately.

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 input schema contains zero parameters. According to the rubric, 0 parameters warrants a baseline score of 4. The description appropriately does not invent parameter semantics where none exist.

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 ('Opens the browser') and resource ('checkout page') to clearly identify this as the payment finalization step. It effectively distinguishes itself from sibling cart management tools (add_items_to_cart, view_cart, clear_session) by specifying the checkout context and payment intent.

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 'so you can select a delivery time and pay' implies this is for the final purchase phase, providing implicit context for when to use it. However, it lacks explicit prerequisites (e.g., 'use after adding items to cart') or guidance on when not to use it (e.g., empty cart scenarios).

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