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

Annotations only declare readOnly=false, destructive=false, idempotent=false; the description adds materially more — that no change occurs until a human approves the exact request and execute_approved_action is called, and that org admins can configure approval requirements. It stops short of saying what happens on duplicate items or whether appending is additive-only.

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?

Four sentences, front-loaded with the action, then the approval gate. The first sentence carries some filler ("RetailHardHat purchase_lists records") but the rest earns its place by spelling out the two-step approval flow.

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 no explanation, and the deferred-approval model is well covered. But for a tool taking a 13-field nested item payload with zero schema descriptions, the description leaves an agent unable to know what to put in `data` beyond required itemName.

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% for 2 parameters, one of which is a nested object with 13 fields (itemName required, qty, actualCost with a decimal pattern, pictureUrl, etc.). The description explains none of these — not which template templateId identifies, not which fields are required, not the cost format — so it does not compensate for the coverage gap.

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: "Append an item to a purchase template." That is clearly distinguishable from create_purchase_template or update_purchase_template_item. It does not, however, contrast itself with the close sibling replace_purchase_template_items, which also writes template items.

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 description gives a prerequisite workflow (approval in Settings > MCP then execute_approved_action), which is real usage guidance, but the opening line ("Use this when working with RetailHardHat purchase_lists records") is generic and does not say when to choose add vs. replace vs. update for template items.

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