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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely new behavioral context: it requires account authorization and explicitly excludes email addresses and birth details, which preempts an agent trying to derive contact or PII from the response.

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 tight sentences, front-loaded with the return contract before the authorization and exclusion constraints. Every clause carries information an agent would otherwise have to guess at; nothing is padded.

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 zero-parameter, read-only identity tool with an output schema and full annotation coverage, the description supplies the remaining essentials: auth requirement, no selectors, and explicit PII exclusions. An agent can call this correctly with no further information.

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?

Zero parameters, so the baseline is 4. The description reinforces this with "accepts no account selectors," making clear that no identifying argument should be supplied — useful because an agent might otherwise assume it must pass an account ID.

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 ("Returns") and a specific resource ("the connected Novamris account's stable opaque identifier and optional display name"), leaving no ambiguity about output. It is unmistakably distinct from the sibling chart/timing tools, which all operate on astrological data rather than account identity.

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?

"for account recognition across reconnects" gives a clear situational trigger for calling it, and "accepts no account selectors" signals there is nothing to configure. It stops short of explicitly naming an alternative or a when-not-to-call condition, but no sibling plausibly competes for this job.

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