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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, so the mutation/safety profile is covered structurally. The description adds that the saved record plus SyncToken is returned, which is useful since there is no output schema, but it says nothing about duplicate handling, required fields, permissions, or error behavior.

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 short sentences, front-loaded with the action and followed by the return value. No filler or redundancy.

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 create tool with a nested entity object and no output schema, the description covers the action and the return value but omits duplicate-prevention guidance, required-field expectations, and failure modes. Combined with the schema's full parameter documentation, it is adequate but has clear gaps.

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%: the schema documents both 'entity' (including the sensitive-data warning about SSNs, tax IDs, birth dates, card details) and 'company'. The description adds no parameter-level meaning beyond that, so the baseline of 3 applies.

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 ('Create a vendor in QuickBooks Online'), which cleanly separates it from update_vendor, search_vendors, and create_customer in the sibling list. It is clear but does not explicitly name an alternative or clarify edge cases such as duplicate vendors.

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?

There is no when-to-use or when-not-to-use guidance. The agent is not told to search_vendors first to avoid duplicates, nor what preconditions (e.g. a connected company) are needed. Only the purpose is stated.

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