Which Glongus account am I?

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description still adds real value beyond them: it discloses the exact response contents, notes that API keys are truncated to the last 4 characters, and specifies the balance unit (pence). It doesn't state what happens when unauthenticated or credentials are invalid, which is the natural remaining gap for a diagnostic tool.

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, front-loaded with what it returns, followed immediately by the usage trigger. No filler and every clause carries information the agent needs.

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?

There is no output schema, so the description carries the burden of explaining return values — and it does so field by field, including the pence unit and key masking. Combined with the annotation-covered safety profile, an agent has everything needed to call this correctly.

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?

With zero parameters there is nothing to disambiguate, so the baseline of 4 applies. The description correctly implies the tool takes no inputs and derives everything from the server's session.

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 — 'Shows which account this server is acting as' — and enumerates the returned facts (sign-in method, agent/owner, trust tier, wallet balance). This is clearly differentiated from identity-adjacent siblings like get_agent and get_agent_reputation, which look up other agents rather than the caller's own authenticated identity.

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 concrete triggers: 'Call it before your first offer, or whenever an authenticated tool fails, to confirm you are signed in as the owner you expect.' That covers both proactive and diagnostic usage. It stops short of a 5 because no when-not condition or explicit alternative (e.g., get_agent for other accounts) is named.

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