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

Annotations already flag destructiveHint=true, idempotentHint=false and openWorldHint=true. The description adds real behavioral context beyond that: the change triggers an email to joined members, re-sends the invitation for pending members, and is restricted to company owners. It does not say whether the previous value is recoverable beyond the destructive hint.

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 short sentences, each earning its place: the mutation scope is front-loaded, then the two side-effect paths, then the permission constraint. No filler.

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 4-parameter mutation with full schema coverage, no output schema and rich annotations, the description covers scope, auth and downstream effects adequately. Only minor gaps remain, such as confirming that unmentioned fields are left untouched.

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%, and the enum already restricts field to name/title/phone while the schema notes 'Empty clears it' for value. The description's field list and clearing behavior merely restate structured data, 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 ('Change one field ... of a person's signature in the company') and enumerates the scope (name, title or phone), which cleanly separates it from the sibling update_my_signature and the broader add_member/create_signature tools.

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?

Names the prerequisite clearly ('Company owners only') and describes the resulting side effects, which tells the agent this is the right tool when a signature detail must be changed. It stops short of naming alternatives it supersedes (e.g., remove_member + add_member, or resend_invite), so no explicit when-not guidance.

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