approve_purchase_order

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

Annotations only declare this as a non-idempotent, non-destructive write; the description adds the critical policy that approval happens as the configured user and never as the requester, plus the preview-code gate. It omits failure behavior for missing/invalid codes and says nothing about reversibility of an approval, which matters for a non-idempotent mutation.

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?

Front-loads the action and the actor constraint before the Args block, and every line conveys something actionable. The docstring-style Args formatting is slightly mechanical but not wasteful.

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 described, and the description covers the actor identity rule and the two-step preview/confirm flow. It lacks any statement of what happens on an invalid or absent confirmation_code and whether a completed approval can be undone.

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 0%, so the description carries the load, and it defines all three parameters: po as the purchase order ID, confirmation_code with its exact source expression, and comment as optional. The po format/example is still unspecified, leaving a small gap the schema does not fill.

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 and resource ('Approve a pending purchase order') and narrows scope to pending POs, which separates it from amend/cancel/reject siblings. It stops short of naming those siblings explicitly, so an agent must infer the boundary rather than read it.

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?

Establishes a clear prerequisite: approval requires a confirmation_code obtained from preview('approve_purchase_order', <same args>), which routes the agent through the correct prior tool. It does not say what to do when the PO is not pending or when no code is available, so exclusion cases are unstated.

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