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

Goes well beyond the annotations by disclosing replace semantics for the top-level fields, that tax profile and omitted invoice preferences survive the write, and two irreversible lock rules (starting number locks after first issuance; currency locks after financial records exist). Those lock facts are exactly the irreversible side effects that destructiveHint=true only hints at.

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 short, front-loaded sentences with no filler: identity/scope first, then preservation, then optional capabilities, then locking constraints. Slightly telegraphic phrasing ('Owner: create or replace...') but nothing is redundant.

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?

For a destructive, idempotent, nested-object mutation with no output schema, the description covers scope, preservation, and irreversibility well. It never states what the call returns or how a partial update interacts with fields outside the listed set, which is the remaining gap.

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 33%, but the description names every nested invoice_preferences field (prefix, padding, starting number, default note, payment instructions) plus the address, compensating for the gap. The two undocumented-by-description params (request_id, business_id) are the ones the schema itself already describes.

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 ('create or replace business name, currency and address') and scopes it to the owner, which separates it from business_get/businesses_list reads and from tax_profile_set (whose data it explicitly preserves). The fields it writes are enumerated, so an agent can tell immediately what this tool mutates.

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 'Owner:' prefix and 'using confirmed facts' set a precondition (caller must own the business and must have verified values), and the note about preserving tax profile implicitly routes tax changes to the sibling tool. No explicit when-not guidance or named alternative is given, so it falls short of a 5.

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