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

Annotations only carry readOnlyHint, so the description's disclosure that identity comes 'from the API key' adds real auth context an agent needs. It also surfaces the underlying GraphQL query name, though it says nothing about failure modes (e.g. missing/invalid key).

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 clauses, front-loaded with the primary purpose, then the returned fields, then the usage hint. Nothing is padded or repeated from structured fields.

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?

With no output schema, the description correctly carries the return shape (user plus orgs' eid/name/slug), which is enough to invoke and consume the result. It could mention error/empty behavior but is otherwise sufficient.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate beyond confirming implicit API-key-based selection. Baseline 4 applies for a no-parameter tool.

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 ('Get the authenticated Anvil user') plus the secondary payload (organizations with eid, name, slug). This clearly distinguishes it from sibling org-scoped tools like anvil_get_organization.

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?

'Good first call to discover org slugs/eids for other tools' gives explicit workflow context for when to reach for it. It stops short of naming a when-not condition or an alternative tool, but the positive guidance is concrete.

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