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

Beyond the annotations (destructiveHint=true, openWorldHint=false), the description discloses the optimistic-concurrency contract — a stale SyncToken will fail — and states the return payload includes the new SyncToken. It does not warn about the destructive sparse-vs-full behavior, but that detail lives in the schema's entity description, so the omission is minor.

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?

Two tightly packed sentences: the action and its prerequisite come first, the return contract second. Nothing is padded and nothing extraneous is included.

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 correctly compensates by describing the return value (saved record plus new SyncToken), and it covers the required prerequisite. The destructive sparse-update caveat is only in the schema text, so the description is slightly thin for a destructive write, but it is largely complete.

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 100%, including the rich sparse/full-update semantics and the prohibited-field list, so the schema carries the parameter burden. The description only restates the Id/SyncToken requirement already in the schema, adding no new 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?

States a specific verb and resource ('Update an existing company info in QuickBooks Online'), which cleanly separates it from get_company_info and search_company_infos. It does not, however, explicitly distinguish itself from update_preferences, the other company-level write sibling, so it falls 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?

The description gives the key prerequisite for calling it: an Id and the current SyncToken 'as the last search or write returned it,' which tells the agent to fetch first. There is no explicit when-not guidance or named alternative tool, so it stays at a 4 rather than 5.

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