whoami

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

Annotations already declare readOnly, idempotent, non-destructive, open-world, so safety is covered. The description adds real diagnostic context beyond that: it is a preflight/failure-triage tool and it reports scope-derived tool availability, which an agent could not infer from the annotation set. It does not describe the response shape, but with no output schema this is a modest omission rather than a blocker.

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 sentences, zero filler. What it reports comes first, the actionable routing instruction ('call this first on 401/403') is last and easy to scan, so the agent gets payoff and trigger in one pass.

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-argument diagnostic tool with full annotation coverage, the description supplies everything an agent needs: what it inspects, why the result matters (which tools are ruled out by scopes), and when to invoke it. No output schema exists, yet the return contents are summarized in prose, so nothing essential is missing.

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 there is nothing for the description to disambiguate; baseline 4 applies. The description correctly implies no input is needed by framing the tool as a pure connection inspection.

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 (check) and resource (the Sentry connection/token), then enumerates the exact facts returned: user identity, token scopes, organization reachability, and which tools the scopes rule out. This is unmistakably the diagnostic/identity tool and is differentiable from every sibling, which are all data-fetching or mutation tools.

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 an explicit trigger condition: 'Call this first when other tools fail with 401/403,' which is exactly the situation an agent needs routing for. It stops short of stating when NOT to call it (e.g. whether it is worth calling preemptively before a long workflow), leaving a small gap, but the primary usage signal is clear.

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