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

Annotations declare readOnlyHint=true, consistent with the read nature. The description adds 'Bulk support: accepts transaction_ids for batched execution,' which is useful but lacks details on batch behavior (e.g., how results are aggregated). No contradictions with annotations.

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?

The description is verbose and unfocused, listing all legacy API actions instead of solely describing the subscription listing tool. The 'Ações:' list is irrelevant and the flattening note adds confusion without clarity.

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?

Given no output schema and the tool's complexity (multi-parameter, bulk support, legacy context), the description omits critical details: return format, how filters work in 'data', what batch execution entails, and error handling. The agent lacks enough information to use the tool correctly.

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?

With 0% schema description coverage, the description must compensate. It mentions 'data' for filters but the schema defines 'data' as a string, not a JSON object, causing mismatch. 'account', 'transaction_id', and 'transaction_ids' are barely explained. The agent cannot infer parameter usage or constraints.

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 conflates multiple legacy API actions (list_transactions, list_subscriptions, etc.), making it unclear that this tool is specifically for listing subscriptions. The 'Flattened action: list_subscriptions' note is confusing; the agent cannot determine if this tool performs only that action or is a catch-all.

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?

Mentions that this tool activates for legacy keys (ak_…) migrating from V5, which provides some context on when to use it. However, it does not explicitly contrast with sibling tools like 'pagarme_subscriptions_list' (non-legacy) or state when not to use it.

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