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

With readOnlyHint/openWorldHint already declaring safety, the description adds real value: full-scan paging behavior without filters, strict AND matching when filters are present, and the business meaning behind each status value (pending = issued/open, partial = partially paid, unpaid = overdue reminder state). It omits return shape and page-size limits, but those live in the schema.

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 sentences, front-loaded with the core verb+resource and field list, followed by filter and status semantics. Every clause carries information an agent would otherwise have to guess.

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 12-parameter, zero-required list tool with no output schema, the description compensates well by naming the returned fields and describing pagination and filter combination rules. What remains thin is the return envelope (e.g. what next_offset/total fields come back), though offset's schema text partly covers that.

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, and the description earns above that by expanding the status enum into business semantics and clarifying that multiple filters combine conjunctively rather than loosely. It adds no detail on ordering, date-range fields, or offset/limit, which the schema already covers.

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 (list/search) and resource (sales invoices) and enumerates the fields returned (number, contact, totals, open amount, dates, status), which makes it distinguishable from bexio_get_invoice and from list_orders/list_quotes. It never explicitly contrasts with those siblings, so it stops 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 explains filter behavior (no filters = page through everything, filters = AND semantics), which implies when the tool is appropriate for browsing vs. targeted lookup. It gives no explicit routing guidance such as 'use bexio_get_invoice for a single invoice' or 'use bexio_list_invoice_payments to see payments', so the agent must infer alternatives.

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