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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the mutation safety profile is covered. The description adds genuine context beyond that: partial-update semantics and the fact that the logo is preserved, which an agent could not infer from the annotations.

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 tight sentences with the core action front-loaded and no filler; every clause (field scope, partial update, logo retention) carries information.

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?

An output schema exists, so return values need not be described, and annotations cover the safety profile. What remains is minor: no statement of error behavior for a nonexistent client, and the 'logo is kept' note references a field that has no corresponding parameter.

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 100%, so all four parameters (including the required 'client' identifier and the 'empty string clears it' semantics for address/legal_name) are already documented. The description restates the editable fields but adds no format or identifier syntax 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 ('Rename a client', 'change the legal name and address') and names the exact fields that can be edited, which cleanly separates it from create_client, archive_client, and get_client without opening any schema.

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?

The description implies usage through its partial-update framing ('Only the fields you pass change'), which tells the agent this is for edits rather than creation. However, it names no alternative tools and gives no when-not guidance (e.g. use archive_client to retire a client), so usage is only implied.

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