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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds no behavioral context of its own: it says nothing about what happens when the Id does not exist, error behavior, or the shape of the returned deposit. There is no output schema to compensate.

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?

A single front-loaded sentence with no padding, though the trailing 'when no search or write answer already holds it' clause is awkwardly worded and slightly obscures the intended routing rule.

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 read-only single-record fetch with full schema coverage and annotation-covered safety, the essentials are present. However, with no output schema, the description should at least hint at the return shape and not-found behavior, and it does not.

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%, so both the 'id' and 'company' parameters are already fully documented in the schema. The description's 'by Id' phrasing adds nothing beyond what the schema states; 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?

States a specific verb and resource ('Get a single deposit ... by Id') scoped to QuickBooks Online, which cleanly separates it from list/search siblings. It gestures at search_deposits ('when no search ... already holds it') but never names it, so the differentiation is implied rather than explicit.

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 clause 'when no search or write answer already holds it' gives a conditional hint to prefer search/create paths first, which is real usage guidance. But the alternative tool is never named and the condition is vague, leaving the agent to infer that search_deposits is the preferred path.

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