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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered; the description adds real context beyond them by naming what the tool excludes (analytics, usage stats, billing) and the zero-balance operational consequence. It stops short of other useful traits such as whether the balance is per-account or shared, units/currency, or any rate-limit or caching behavior.

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?

Three tight sentences: purpose first, then when-to-use, then return/exclusion/gating. No filler, and the most agent-relevant constraint (zero balance blocks publishing) is surfaced rather than buried.

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 an output schema present, return values need not be enumerated, and annotations cover the safety profile. What remains — when to call, what it excludes, and the zero-balance consequence — is all stated, so an agent can call it correctly without further inference.

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 the baseline is 4; there is nothing for the description to disambiguate. The description correctly implies the call is scoped implicitly to the authenticated account, which is the only semantic question a parameterless call raises.

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 and resource ('retrieve the current credit balance of the authenticated Blog2Social API account'), which is immediately actionable. It also delimits scope by negation ('does not provide individual post analytics, account usage statistics, or billing details'), effectively distinguishing it from siblings like posts.insights and account.overview.

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?

Gives explicit trigger conditions ('when the user asks about available credits') and a proactive precondition ('before an action that may consume credits, such as publishing or retrieving post insights'). It also names a hard gating rule: publishing is not possible at zero balance, which is directly decision-relevant for an agent orchestrating calls.

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