Get client

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

Annotations already cover readOnly, idempotent, non-destructive and openWorld, so the safety profile is done. The description adds genuinely useful context beyond that: the underlying endpoint (GET /clients/{id}) and, importantly, that sensitive PII (email, landline, mobile, DOB, NIN) is withheld unless include_contact_details is set. It does not say what happens for an unknown ID.

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?

Three tight sentences, front-loaded with the core purpose and ending on the parameter caveat. The field enumeration is information-dense rather than padding, and nothing is wasted.

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 description carries the burden of describing the return shape, and it does so adequately by listing the returned fields. For a simple two-parameter read tool with strong annotations this is nearly complete; only error behavior for a missing/invalid ID is unaddressed.

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 both parameters are fully documented in the schema, including the exact fields gated by include_contact_details. The description restates that the contact fields are conditional but adds no format, range, or default nuance beyond the schema, 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 verb and resource (fetch one client by ID) and enumerates the returned fields (name, decision status, reference, archived flag, retention date, timestamps), so the agent knows exactly what it gets. It separates itself from list_clients by the singular 'One client by ID', though it never names that sibling 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 implied rather than stated: you need a known client_id and want a single client rather than a list. The description does give real conditional guidance for include_contact_details ('only with'), which is the closest thing to explicit when-to-use. It offers no exclusions or named alternatives.

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