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

With annotations already declaring destructiveHint=true and readOnlyHint=false, the description adds genuine context beyond them: null clears an optional field, and a new hourly rate only applies to time logged going forward while already-logged entries keep their original rate. This is valuable behavioral detail. It stops short of stating permissions or reversibility.

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, both front-loaded and information-dense; the field enumeration comes first and the rate-behavior caveat follows. No filler and every sentence earns its place.

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 mutation tool whose annotations carry the destructive profile and with no output schema, the description is nearly complete, covering what can be changed and the side effect of clearing fields. Minor gaps remain around permissions and whether individual changes are reversible.

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 low (22%), so the description must compensate. It meaningfully groups the updatable fields and adds the crucial 'null clears an optional field' semantics absent from the schema, but it does not map semantics to each of the 9 params (e.g., taxId, address are only loosely implied under 'contact details').

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 states a clear verb ('Changes') and resource (a client's fields), enumerating the updatable attributes (name, contact details, currency, hourly rate, notes). It is unambiguous about what the tool does, though it does not explicitly distinguish itself from siblings like create_client or archive_client.

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: use it to modify an existing client's fields. There is no explicit when-to-use/when-not framing and no mention of alternatives (archive_client for removal, update_client_portal for portal settings), leaving routing to inference.

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