Read a customer's payment settings

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

With no annotations provided, the description must carry the behavioral burden, and it does so by explicitly declaring 'Read-only' and listing the data fields included in the response. It also explains that this tool aggregates settings that the set_* tools each modify, which is informative beyond the schema. It does not mention authentication or error behavior, but for a simple read on a single reference this is a minor gap.

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 two sentences with no filler. The first sentence states the action and enumerates the returned fields; the second sentence reinforces the read-only nature and links to the mutating tools. Every clause earns its place and key information is front-loaded.

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 single-parameter read tool with no output schema, the description provides the essential return contents and explicitly frames the tool in relation to its writing counterparts. An agent can correctly infer what to expect and when to choose this tool. Nothing critical for a basic call 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?

The only parameter, customer_ref, is already fully described in the schema with 100% coverage, so the description does not need to add syntax or format details. The description focuses on the return content rather than the parameter, which is appropriate. This matches the baseline of 3 for high schema coverage.

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 opens with a specific verb and resource: 'Reads the payment settings of a ProAbono customer in one call.' It enumerates the exact fields (payment type, billing mode, grey-list status, invoice note, next billing date), making the tool's scope unmistakable. It also names the sibling write tools, so an agent can distinguish this read operation from the set_* family without inspecting those schemas.

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 explicitly labels the tool as read-only and points to set_payment_method, set_invoice_note, and set_next_billing_date as the tools that write the same fields. This gives clear direction for when to use this read endpoint versus its mutation siblings. It stops short of formal 'use this when... not when...' phrasing, but the context is strong enough for an agent to route correctly.

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