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

No annotations exist, so the description carries the full burden. It discloses side effects: records conversion in telemetry, ends the attribution session, and returns order confirmation with order ID and receipt link. This gives the agent useful behavioral expectations, though it does not mention idempotency or error behavior.

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 concise sentences, each serving a distinct purpose: action, condition, return value. No unnecessary wording, and the key information is front-loaded.

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?

The description covers purpose, when to use, side effects, and return information. An output schema exists, so return details are not needed. It could include error handling or idempotency, but for a low-complexity tool with full schema descriptions, this is sufficiently complete for an agent to invoke it correctly.

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 coverage is 100% (both parameters have descriptions). The tool description adds minimal parameter-specific info beyond the schema, only reinforcing that session_id should match the one from search/checkout. Baseline of 3 is appropriate as the schema carries the parameter meaning.

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 clearly states the action: 'Complete a checkout and place the order.' It distinguishes from sibling tools (start_checkout, update_checkout_info) by specifying a precondition (checkout status 'ready_for_complete') and unique side effects (records conversion, ends attribution session).

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?

Provides an explicit condition for use: 'Only call this when the checkout status is ready_for_complete.' It does not name alternative tools, but the condition implies that other tools are needed for other states. This is clear context but lacks explicit exclusions or alternative references.

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