List clients

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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so the safety profile is covered. The description adds real behavioral context beyond that: the redaction rules that are lifted by include_contact_details (emails, phones, NI numbers, UK postcodes) and the note that bank/card numbers are always removed, plus the wire-level mapping of 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 sentences, no filler, with the resource and returned fields front-loaded before the filter and include semantics. The second sentence is dense with sub-clauses but each clause carries distinct information, so 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?

For an 8-parameter, no-required-argument list tool with no output schema, the description covers the returned fields, the filter set, and the one parameter with privacy implications, which is enough to call it correctly. Missing only an explicit note that pagination is driven by the schema's start_page/max_pages, which the schema already explains.

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 coverage is 75%, so the schema documents most parameters, but the description adds value by mapping the friendly filter names to the wire parameters actually sent (id, costCentreCode, clientCategoryCode, ModifiedSince) and by explaining the compounded side effect of include_contact_details. It stops short of describing pagination interaction (start_page/max_pages), which the schema covers.

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 names a specific verb+resource ('Clients (GET /clients)') and enumerates the returned fields (code, name, category, cost centre, currency, payment terms, invoicing settings, notes), so an agent immediately knows it is a client-listing read. It does not explicitly differentiate itself from the sibling list_* tools, but the resource noun is unambiguous.

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?

It documents which filters exist and the conditional behavior of include_contact_details (which also sends include=address,billing), which implies when to reach for that flag. However, there is no explicit 'use this when' statement and no routing to sibling tools (e.g. list_projects for project data); the agent must infer context from the resource name alone.

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