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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds real value beyond them: it discloses the gate-enforced authorization model and that `_auth` cannot be supplied or forged by the client, which matters for trust. It does not say what the returned account object contains (id, email, roles), and no output schema exists to fill that gap.

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?

Two short sentences, front-loaded with the identity of the returned resource, followed by the deployment constraint. No filler, though the stray line break mid-sentence slightly hurts structure.

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 no output schema, the description is nearly sufficient but leaves the return shape unspecified — an agent cannot predict whether it receives a username, email, or a token/claims object. Adding one clause about the returned fields would close the only real gap.

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 the schema baseline of 4 applies. The description correctly notes the client cannot supply `_auth`, which preempts an agent from trying to pass an identity argument — a useful clarification 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?

The description names a specific resource — the signed-in account as verified by the gate — which is unambiguous and cannot be confused with any sibling tool (evaluation, docs, benchmarks). It is phrased as a noun clause rather than a verb, so the action (retrieve the current identity) is implied rather than stated, but the purpose is still clear.

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?

Usage is only implied: the tool is available on the gated `/mcp/connect/` endpoint, so it is for callers on that surface. There is no explicit 'use this when you need to know which account is acting' guidance, nor any statement about when not to use it or what to do instead — though with no comparable sibling, alternatives are naturally absent.

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