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

Annotations already establish that this is a read-only, idempotent, non-destructive operation, so the bar is lower. The description adds only the grouping dimensions and leaves unexplained what 'reviewed' means, how currency is handled, or what defaults apply.

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 single-line fragment is concise and front-loads the grouping dimensions, but it lacks an action verb and is too terse for an ambiguous reporting tool. It avoids waste but sacrifices clarity.

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 no output schema, the description should clarify the return shape, but it does not say whether the result is a transaction list or a summary, how date defaults work, or what 'reviewed' filters. An agent cannot reliably predict the output from this definition.

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 four optional filters are already documented in the input schema. The description loosely echoes vendor and category and implies date/month handling, but adds no syntax, default, or combination semantics beyond the schema.

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 identifies the subject as reviewed spending broken down by category, month, vendor, and currency, but it uses no explicit verb and does not make clear whether the tool returns individual purchases or an aggregated report. This vagueness makes it hard to distinguish from purch_spend or purch_transactions without opening the 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?

There is no guidance on when to use this tool versus alternatives such as purch_spend, purch_transactions, or purch_card_costs. No exclusions, prerequisites, or routing hints are provided.

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