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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds real behavioral context beyond them: results are newest-first, pagination is a bounded page plus a cursor, and pending rows are absent from spending totals. It stops short of rate limits or the hard page-size cap (that lives in the schema), so a 4 is fair.

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 sentences, front-loaded with the core resource and scope before routing and the pending clarification. Every sentence earns its place, though the definition of PENDING partially duplicates the schema's own status description, which is the only mild redundancy.

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 need not document return values, and it correctly limits itself to ordering, pagination, routing, and the pending nuance. For a 9-parameter filtered-list tool with read-only annotations, nothing an agent needs to call it correctly is missing.

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 every parameter including the enum semantics and the sign convention for min-amount is already documented. The description reinforces the period filter and ordering but adds little syntax or format meaning that the schema does not already carry, so the 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 names a specific verb and resource ('the household's actual transactions over a period, newest first') and states its exact scope, including ordering and optional filters. It explicitly distinguishes itself from spending_by_category and monthly_trend by framing the question type ('which ones' vs 'how much'), so an agent can route without opening any 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?

It gives explicit when-to-use guidance ('which ones' rather than 'how much'), names the two cheaper alternatives for totals, and adds a second use case (finding pending charges) with the reason totals can't answer it. This is a textbook routing instruction with no inference required.

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