List account activity

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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds genuinely new behavioral context beyond that: results are ordered newest first and each entry carries merchant, amount and card. It does not discuss result windowing, how far back 'recent' reaches, or error behavior when the account ID is unknown, which keeps it off a 5.

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 sentence, front-loaded with the verb and resource, that also packs in ordering and payload contents. Every clause earns its place and nothing is repeated from the schema or annotations.

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 simple two-parameter read tool with no output schema, the description carries the important return-value information (newest first, merchant/amount/card fields) that would otherwise be missing. The remaining gap is minor: no statement of how far back activity extends or what an empty result means.

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%, with both financialAccountId and limit (including its 1-100 bounds and default of 20) fully documented in the schema. The description references the account implicitly but adds no meaning beyond that. Baseline 3 is appropriate when the schema does the heavy lifting.

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 pairs a specific verb ('List') with a specific resource ('recent activity on a financial account') and adds scope detail: 'newest first', and the activity types 'authorizations and clearings with merchant, amount and card'. That is far more informative than the title alone. It stops short of naming a sibling to distinguish itself from, so a 4 rather than a 5.

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?

Usage is only implied: the tool is evidently for inspecting recent transactions on a known account, and the required financialAccountId makes that context obvious. There is no explicit when-to-use, when-not-to-use, or pointer to a sibling such as get_financial_account for account metadata. Minimum viable rather than instructive.

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