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 genuinely new behavioral context: the output is report-style data grouped by account rather than a flat transaction list, and there is an implicit 90-day lookback window. It does not mention pagination behavior beyond the schema's limit default.

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?

Four short sentences, each earning its place: purpose, output shape, default window, and alternative routing. The most decision-relevant information (what it returns, the default range) 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?

There is no output schema, but the description compensates by stating the return shape ('report-style data grouped by account'). Combined with the default date window and the sibling routing rule, an agent has everything needed to call this tool correctly.

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 all four parameters are already documented, which sets the baseline at 3. The description goes beyond the schema by specifying the 90-day default date window, which the schema does not state for dateFrom/dateTo, adding real parameter-level value.

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 ('Search accounting ledger transactions') plus the grouping scope ('for a company'). It explicitly names the sibling it is not (search-transactions), so an agent can disambiguate the two without opening either schema.

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?

Gives an explicit routing rule: use search-transactions instead when transaction IDs are needed for commenting. It also states the default behavior (last 90 days) that applies when no date range is supplied, which is the main decision an agent must make when calling this tool.

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