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

readOnlyHint=true already establishes this as a safe read, so the description needn't restate safety. It adds useful context about the returned payload shape (contact details and custom fields), but says nothing about not-found behavior, errors, or permissions.

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 short sentences with no filler; the what-it-does statement is front-loaded and the endpoint notation follows compactly.

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 simple single-parameter read tool with no output schema, the description sufficiently covers what is fetched and the resource identity. Minor gaps around error/empty results remain but are not required for correct invocation.

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% with a single required customer_id, so the schema fully documents the parameter. The description only echoes the identifier via the GET /customers/{id} path, adding no new semantics such as accepted ID forms.

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 (Retrieve) and resource (one customer), and clarifies that a customer is a family or independent student plus what is returned (contact details, custom fields). It implicitly contrasts with the singular-vs-list sibling teachworks_list_customers through 'one customer', but never names an alternative explicitly.

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 by 'Retrieve one customer' plus the REST path, so an agent can infer this is a by-id lookup. No guidance is given on when to prefer this over teachworks_list_customers, teachworks_get_student, or teachworks_get_employee, and no prerequisites are stated.

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