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

Annotations indicate readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds important behavioral traits beyond annotations: SCA-protected (signed internally via private.pem), maximum window of 469 days, and bulk support via profile_ids/balance_ids. This provides transparency about security constraints and limits. No contradiction 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 concise, using two paragraphs that front-load the most critical information (purpose and uniqueness) followed by limitations and bulk support. Every sentence adds value, though the second paragraph on bulk support could be integrated more smoothly. Overall, it is efficient and well-structured.

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 the complexity (9 parameters, no output schema), the description provides adequate context: purpose, unique value, limitations (469 days, SCA protection), and bulk support. However, it lacks details on return format and parameter specifics, which would be helpful for an agent. Still, it covers the essential context for selection and usage.

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?

Despite zero schema description coverage (0%), the description does not explain individual parameter meanings beyond listing them. It mentions required parameters (profile_id, balance_id, currency, interval_start, interval_end) and optional ones (type, account, balance_ids, profile_ids) but provides no further semantics, data types, or format expectations. The description adds minimal value for parameter understanding.

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 explicitly states the tool returns a full statement of a balance including specific transaction types (deposits, withdrawals, conversions, fees, interest, and crucially CARD_TRANSACTION). It emphasizes that this is the only Wise endpoint that exposes card transactions, clearly distinguishing it from siblings like wise_get_card_transaction (which is for a single card transaction) and wise_list_activities (which lists general activities).

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 description provides clear context on when to use this tool: it is the unique endpoint for card transactions and is the reason this MCP exists, comparing to the alternative 'Wise connector da Pluggy/Open Finance brasileiro' which does not include card events. It also mentions bulk support and a maximum window of 469 days. However, it does not explicitly state when NOT to use it (e.g., if no card transactions needed), but the unique value proposition is clearly communicated.

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