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

readOnlyHint=true already declares the safety profile, and the description goes beyond it by disclosing the returned payload (addresses, contact data, bank accounts) and the underlying API endpoint. That return-content detail is genuinely useful since no output schema exists.

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?

A single front-loaded sentence stating the resource and its returned contents, followed by the endpoint path. Efficient, though the raw endpoint string is marginal value for an agent.

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 one-parameter read tool with annotations covering safety and no output schema, the description supplies the missing return-shape information (addresses, contacts, bank accounts), which is what an agent most needs here. Only the list-then-get relationship is left implicit.

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?

There is only one parameter and schema description coverage is 100% — the schema already documents the id and its provenance from cashctrl_list_persons. The description adds no format or constraint detail beyond it, so the baseline 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?

States a specific retrieval verb implicitly ('One person or company by id') and names the resource, plus enumerates the payload contents (addresses, contact data, bank accounts). An agent can distinguish it from cashctrl_list_persons by the singular scope, though the description never explicitly contrasts the two.

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?

Usage is only implied: the schema note '(from cashctrl_list_persons)' hints at the list-then-fetch flow, but the description itself gives no when-to-use statement or alternatives. Adequate but leaves the agent to infer the workflow.

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