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

Adds real value beyond annotations: the code is short-lived and single-use, and the call is permission-gated to owner/coordinator. Annotations already declare readOnlyHint=false, idempotentHint=false, destructiveHint=false, so the 'This is a write' line is redundant but harmless. It leaves open what happens to a previously issued code when a new one is minted, which matters given idempotentHint=false.

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, front-loaded with the action and output artifact, followed by the downstream use and the authorization gate. No filler; each sentence carries distinct 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?

For a single-parameter write tool with no output schema, the definition covers purpose, audience, authorization, and lifespan of the code. The minor gaps are the return shape (does it return the code string, an expiry?) and the actual TTL of 'short-lived'.

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?

With one parameter at 100% schema description coverage ('loved one id from list_loved_ones'), the schema already carries the semantics, so the baseline is 3. The description adds only a mild constraint that the loved one must be in 'this household'.

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 precise verb+resource: mints a short-lived, single-use provider/vendor link code for one loved one in the household. That is clearly distinguishable from the read-oriented siblings (list_loved_ones, get_inbox_message) and from invite_family_member, which targets a different audience.

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?

Gives concrete when-to-use ('Hand the code to a LovedOne Soft agency so they can link that person as a client') and an explicit exclusion ('Owner or coordinator only — viewers are rejected'). It does not name a sibling alternative for adjacent cases, so it falls just short of 5.

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