concur_whoami

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

Annotations already cover readOnly and openWorld, so the bar is lower, yet the description still adds real context by surfacing that the response includes datacenter and session-token expiry — information an agent needs to reason about authentication state. It stops short of saying what happens when there is no valid session (error vs. empty identity), which is the one behavior an agent would most want confirmed.

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?

A single sentence front-loads the core question ('who the session belongs to') and then lists the returned fields after a colon, which reads efficiently. The parenthetical feature list is slightly long but each item is concrete rather than filler.

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 parameters and no output schema, the description carries the burden of explaining what comes back, and it does so field by field. The only missing piece is failure/unauthenticated behavior, a small gap for an otherwise simple identity tool.

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 and the baseline of 4 applies. No parameter meaning is lost or misrepresented.

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 the specific resource (the SAP Concur session and its owning user) and enumerates the exact fields returned: user id UUID, datacenter, token expiry, and feature entitlements. It is clearly distinct from the data-listing siblings such as concur_list_trips or concur_get_report, though it does not explicitly contrast itself with concur_healthcheck, which is the nearest conceptual neighbor.

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?

There is no explicit when-to-use statement or named alternative; the agent must infer that this is an identity/session probe useful before or when other Concur calls fail. The mention of 'minutes until the browser session token expires' implies a session-validation use case, but that implication is never stated as guidance.

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