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

Annotations already declare readOnly, non-destructive, non-open-world. The description goes further and discloses behavior an agent needs that annotations do not: the result is bounded to the first page of up to 100 entries, ordering is by line item, and each record carries only id and amount with no date, accounts, or description. With no output schema present, this is the only place such return-shape limits are communicated.

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, front-loaded with the core behavior, then the constraint on parameters, then the alternative routing. No sentence is filler; every clause carries selection-relevant information.

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 single-parameter read tool with no output schema, the description supplies the missing return-value information (page size cap, ordering, field subset) and the sibling routing. Nothing an agent needs to invoke it correctly is absent.

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%, so the single id parameter is fully documented as the company ID. The description reinforces the limited parameter surface by noting there are no date or paging parameters, but adds no syntax or format detail beyond the schema, so 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?

Specific verb (get) plus resource (journal entries) with explicit scope: first page, up to 100, ordered by line item, only id and amount. It also names the sibling tools it is meant to be distinguished from, so an agent can tell it apart from search-accounting-transactions and get-trial-balance without opening schemas.

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?

Explicitly routes the agent: use search-accounting-transactions for ledger activity in a date range and get-trial-balance for account balances. It also states what this tool cannot do (no date or paging parameters), which is exactly the when-not guidance that prevents wrong selection.

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