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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the read-only, non-destructive nature. The description adds useful context beyond annotations: it explains the record type (accounting record of a bank payment) and explicitly states 'It does not move money,' which reinforces the read-only behavior and prevents misuse as a financial transaction tool. 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 exactly two sentences. The first sentence states the action and target, the second provides domain context and a critical clarification. No fluff, and the most important information is 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?

For a simple get-by-id tool with two well-documented parameters and annotations covering the safety profile, the description is complete. It clarifies the domain meaning and the non-monetary nature. There is no output schema, but that is not a gap for this simple fetch operation. The only slight omission is an explicit pointer to alternatives, but that is not critical for a basic getter.

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 description coverage is 100% – both 'id' and 'company' are clearly described in the schema. The description does not add any parameter-specific information beyond what the schema already provides. Since the schema carries the full burden, baseline 3 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?

The description states a specific verb ('Get'), resource ('credit card payment txn from QuickBooks Online'), and scope ('by Id'). It also clarifies the domain meaning as 'an accounting record of a bank payment toward a credit card balance' and adds 'It does not move money,' distinguishing it from financial operations and siblings like create/update/delete and search.

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 phrase 'Get a single ... by Id' implies this tool is for retrieving one specific record when an Id is known, but it does not explicitly mention alternatives such as search_credit_card_payment_txns for multiple records or filtering. The clarification that it does not move money hints at when not to use it for financial actions, but no direct comparison to siblings is provided.

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