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

Annotations cover the safety profile (readOnly=false, idempotent=false, destructive=false, openWorld=false), and the description adds genuinely useful beyond-schema context: the OAuth requirement, the manager-review delay, an explicit 'do not pay before confirmation' warning, and the fact that the order is bound to the account email. This is more than the annotations already say, though it omits pagination/rate/duplicate-submission behavior for a non-idempotent create.

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?

The purpose is front-loaded in the first sentence, followed by return values, workflow warning, fulfillment modes, and auth requirement. Sentences are dense but each carries a distinct fact; little is wasted.

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?

With no output schema, the description usefully enumerates what is returned (order number, invoice status, page link) and flags the OAuth prerequisite, so return-value understanding is covered. However, given 11 parameters at 18% coverage, the description leaves the caller without enough field-level understanding 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 description coverage is only 18% across 11 parameters, so the description must carry the load, and it largely does not: inn, kpp, company, legal_address, contact, comment, and cart_id are never explained in the description. It adds meaning only for the delivery choice (pickup vs. carrier) and echoes the account-email rule, leaving most required/optional fields undocumented.

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 states a specific verb and resource ('Оформить заказ и запросить счёт') and narrows the audience to legal entities and sole proprietors (юрлицо или ИП), which distinguishes it from generic cart/order siblings. It does not, however, explicitly name which sibling to use for other flows, so it falls just short of a 5.

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?

It supplies real prerequisites (requires OAuth login, invoice is prepared by a manager after review, do not pay before confirmation, pickup or carrier delivery by arrangement), which tell the agent how the tool behaves. But there is no explicit when-to-use vs. alternative routing (e.g. reorder vs build_cart vs this), so guidance is implied rather than comparative.

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