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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description still adds value beyond that by noting the call consumes no credit ('این ابزار هزینه ندارد') and by scoping the returned data, which an agent needs to decide whether calling is worthwhile.

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 short sentences, front-loaded with the resource and its returned fields. The Persian sentence is a near-exact translation of the English one, which is redundant for a monolingual reader but serves a legitimate localization purpose and costs little length.

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 must carry the return-value burden, and it does by naming balance, spend, limit, and rate limits. It stops short of describing response shape or units for the limit fields, but for a zero-argument status tool this is close to sufficient.

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 there is nothing for the description to disambiguate; the schema is empty and fully self-evident. Baseline 4 applies.

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 ('Show') and resource ('Gisoo AI credit balance') and enumerates exactly what is returned: balance in USD, key spend, spend limit, and rate limits. This is unmistakably distinct from every sibling (generate_image, ask_model, etc.), which are generation tools.

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 line 'Free: costs nothing' implicitly signals when the tool is safe/cheap to call and hints at a pre-flight check role, but there is no explicit 'use this before/after X' guidance and no named alternatives or exclusions. Usage is inferable rather than stated.

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