shelf_whoami

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds one useful behavioral fact — that the first workspace in the result is the default — but says nothing about auth requirements, latency, or whether results are cached.

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 with zero filler, and the most decision-relevant fact (what identity and workspace data comes back) is front-loaded. The trailing 'first workspace is the default' is a compact, high-value detail rather than padding.

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 largely compensates by naming the returned fields (user, workspaces, IDs, roles, default ordering). It falls short only on how to interpret the result set (e.g. whether all memberships are returned and how the default relates to subsequent workspace-scoped calls).

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; the baseline of 4 applies. The description correctly describes only return content and does not invent parameter semantics.

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 ('Show') and resource ('the logged-in user and the workspaces (organizations) they belong to'), plus the payload contents (IDs and roles). This is clearly distinguishable from siblings like shelf_set_workspace (a mutation) and shelf_list_team_members (lists other users, not the caller).

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: an agent can infer this is the identity/context call to make before workspace-scoped operations. There is no explicit when-to-use, no when-not-to-use, and no named alternative (e.g. shelf_set_workspace) despite that sibling being the natural counterpart.

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