credit_balance

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

No annotations are supplied, so the description carries the disclosure burden; "Return" does at least establish that this is a non-mutating read. It does not state whether authentication is required, whether the call costs anything, what units the credits are in, or what a zero/exhausted balance looks like in the response.

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 with no filler, hedging, or repetition. There is nothing to trim and nothing important buried later in the text.

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 read with no output schema, the description says what is retrieved but not the shape of the return value (scalar number vs. object with plan/quota breakdown) or behavior at exhaustion. It is minimally sufficient to call the tool but leaves the response format to guesswork.

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 an empty object, so there is no parameter semantics to explain and the baseline of 4 applies. The description adds no misleading argument hints, 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?

"Return the account's remaining hosted credits" names a specific verb (return/read) and a specific resource (hosted credit balance). It is unambiguous about what the tool retrieves, though it does nothing to relate itself to the listed siblings (scrape/map/search), which it plainly differs from.

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 statement of when to call this tool, under what conditions (e.g., before launching a batch scrape, or on quota errors), or how often it should be polled. The usage is only inferable from the resource named, with no explicit guidance.

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