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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds genuinely new context by stating the call is free and 'moves no money', plus disclosing which internal state is inspected (ledger integrity, mock-settlement). It stops short of saying what a degraded/unhealthy response looks like, but it meaningfully exceeds the annotation coverage.

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 front-loaded sentence lists the reported facets, then closes with the cost/safety caveat. Every clause carries information; there is no filler or restatement of the tool name.

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 describing the return content, and the facet enumeration does that well. The only remaining gap is that it doesn't say how failures or unconfigured states are represented in a status snapshot.

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 and the schema is fully closed (additionalProperties: false), so there is nothing for the description to disambiguate. Per the zero-parameter baseline this is a 4; no parameter-relevant detail is missing.

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 a specific resource (GatePay service status) and enumerates exactly the facets reported: health, route-auth configured state, active policy summary, mock-settlement state, ledger integrity. That is far more informative than a generic 'get status', and the read-only diagnostic nature clearly separates it from the action siblings (gatepay_policy, gatepay_quote, gatepay_route), though no sibling is named explicitly.

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: 'Free; moves no money' hints that it can be called casually for pre-flight checks, and the field list implies diagnostic use. There is no explicit when-to-use guidance, no statement of alternatives, and no mention of when a different sibling (e.g. gatepay_policy) should be called instead.

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