Add or update a member

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

Annotations already declare readOnlyHint=false and destructiveHint=false, so mutation is expected. The description adds meaningful behavior beyond annotations: name acts as the case-insensitive key, and only phone/email are updatable. This gives the agent the core upsert semantics.

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?

The description is two short sentences with zero wasted words. The primary operation is front-loaded, and the key identity rule follows immediately.

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 simple three-parameter upsert with an output schema present, the description covers the essential behavioral contract. It could explicitly state that phone/email are optional and that the name field cannot be updated, but the title and key statement largely imply this.

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 only 33%, so the description must compensate. It does: 'Name is the key' clarifies the identity role of the required parameter, and 'update phone/email' maps directly to the optional parameters. It adds case-insensitivity semantics not present in the schema.

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 uses a specific verb pair ('Add or update') with a clear resource ('household member') and identifies the identity key ('Name is the key'). This clearly distinguishes it from sibling tools like get_members and remove_member.

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 makes the tool's context obvious: use it to add a new member or update an existing member's phone/email. It does not explicitly name alternatives or exclusions, but sibling tool names like get_members and remove_member make the boundaries clear enough.

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