Credit status

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

The readOnlyHint annotation already establishes that this is a safe, non-mutating call, so the description needn't restate that. It adds some value by disclosing the shape of the returned information (limit, open tab, owed amount, due date), which is beyond what annotations provide. It does not mention whether figures are live or cached, per-currency handling, or behavior when no credit line exists.

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 short sentence with no filler; every phrase contributes a returned field. It reads as a fragment rather than front-loading an action verb, which slightly weakens the opening.

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 output schema, the description carries the burden of explaining what comes back, and the field list only partly does that job — no indication of currency, format, or structure. For a simple zero-parameter read tool this is marginal but acceptable; it stops short of being sufficient on its own.

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 schema semantics are moot and the baseline applies. Nothing in the description misleads about inputs.

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 resource (Tabula credit line) and enumerates what it returns (limit, open tab, amount owed, due date), so an agent can infer this is a read of account credit state. However, it is a noun phrase with no verb, and it never explicitly contrasts itself with pay_with_credit, which is the adjacent tool an agent might confuse it with.

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 when-to-use guidance at all — nothing says to call this before paying with credit, or that pay_with_credit is the alternative action. The agent must infer usage from the field list alone.

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