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

Annotations already cover read-only/non-destructive safety, and the description adds substantial behavioral detail: status meanings, converted-quote behavior, expiry-date semantics, 100-item page size, cursor pagination, and the required API key. This goes well beyond what annotations provide.

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 description is front-loaded and efficient, but the opening fragment 'Invoice Ninja: Quotes with client, status, valid-until date and amount.' is a header-like sentence that duplicates later field explanations. Otherwise every sentence earns its place.

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 list tool with no output schema and full annotation coverage, the description covers return fields, status semantics, pagination, and auth requirements. Nothing essential for correct invocation is missing.

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 coverage is 100%, so the baseline is 3. The description repeats the status values and explains the 'converted' output but adds little beyond the schema's own parameter descriptions (limit, cursor, status, company, client_id), so it does not lift the score.

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 the verb 'Lists' and resource 'quotes' with scope 'one company, newest first', clearly distinguishing it from invoice-listing siblings. It also enumerates the returned fields (client, status, valid-until, amount), so an agent knows exactly what the tool produces.

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 implies the tool is for listing quotes of a single company but never names an alternative (e.g., list_invoices or get_quote) or explains when not to use it. Context is clear enough to infer usage, but no explicit routing guidance is provided.

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