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

readOnlyHint=true already establishes the safe-read profile, so the description's marginal burden is low. It does add real value by enumerating what comes back (items and allocations are nested-ish data the agent wouldn't otherwise expect) and naming the backing endpoint, but says nothing about paging, ordering, result limits, or default filters.

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 terse fragments, zero filler, with the payload contents front-loaded. The trailing 'GET /credit-notes' is close to noise for an agent that never constructs URLs, and the fragment style omits an explicit verb, but density is good.

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 field enumeration usefully sketches the response shape, which is the right instinct. But for an 8-parameter, zero-required list tool, it omits what an agent actually needs to call it well: pagination flow, whether results are filtered by default, and ordering.

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%, so all eight filters (id_gt/id_lt cursor paging, invoiceId, patientId, update_gt/update_lt, sentStatus, practitionerId) are already documented. The description adds no filtering semantics beyond the schema, which is the expected baseline when the schema does the work.

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 enumerates the fields a credit note carries and appends the endpoint, so it's clear this is a credit-note read, but it never states the verb or scope in prose — the agent relies on the title 'List credit notes'. It also doesn't distinguish this from list_invoices or get_invoice, the nearest siblings in a 33-tool set.

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 guidance at all: nothing says whether to reach for this versus splose_list_invoices or splose_get_invoice, and no mention of paging through results despite pagination parameters existing. The agent must infer usage purely from the name.

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