get_auth_status

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

Annotations declare readOnlyHint=true, so the description doesn't need to restate that. It adds meaningful context beyond the annotation by specifying what the report contains (configured status, source, masked preview), which helps an agent understand the tool's output. There is no mention of side effects, but given the read-only hint, none are expected.

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, no fluff. The first sentence front-loads the core purpose and outputs, while the second sentence gives the practical use case. Every word earns its place, making it easy to scan and understand quickly.

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 diagnostic tool, the description is complete. It tells the agent what it reports, where the information comes from, and when to use it. No output schema exists, but the description's list of reported items (configured status, source, masked preview) sufficiently covers what the agent can expect.

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 has no parameters, and schema coverage is 100%, so the schema fully documents the parameter space. Baseline for such tools is 4, and the description appropriately doesn't try to add parameter details that don't exist. The description focuses on behavior rather than parameters, which is correct.

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 uses a specific verb 'Report' and identifies the exact resource: whether a Splitwise API key is configured, its source, and a masked preview. This clearly distinguishes it from sibling tools like setup_auth and logout, which perform different actions. An agent can immediately understand what this tool does without ambiguity.

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?

The description explicitly states 'Use this to diagnose auth failures,' providing a clear directive for when to call this tool. While it doesn't mention alternatives by name, the intent is unmistakable and aligned with the diagnostic nature of the tool, separating it from setup or logout operations.

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