Audit Credit Card Payments

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds valuable context about transient differences ('small transient differences appear while recent transactions are pending/uncleared') and interpretation notes, confirming it is non-destructive and explaining expected timeliness of data.

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 well-structured with a clear first sentence stating the core purpose, followed by explanatory details. It is appropriately sized but could be slightly trimmed (e.g., 'Interpretation note' is slightly verbose). Nonetheless, it is efficient and front-loaded.

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, the description does not need to cover return values. It covers everything else: what the tool does, when to use it, behavioral notes, and interpretation guidance. Complete for a read-only audit tool.

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?

Schema coverage is 100% and the description of the single parameter 'budgetId' in the schema is adequate ('Budget ID (uses default if not provided)'). The tool description does not add further parameter semantics, but given complete schema coverage, a baseline of 3 is appropriate.

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 clearly states it is a 'read-only audit' comparing credit card balances to payment category balances. It specifies the verb 'audit', the resource 'credit card payments', and uniquely distinguishes itself from sibling tools like get_account or get_transaction by focusing on the audit/reconciliation of payment categories.

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?

Provides explicit guidance: 'Makes no changes — fix shortfalls by assigning to the payment category via update_month_category.' This tells the agent when to use this tool (to identify shortfalls) and when not to, and points directly to an alternative tool for remediation.

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