Transactions changed since

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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so safety is covered. The description adds a genuinely new constraint not present in the schema or annotations — 'within the last year' — plus the kinds of changes that surface (status changes, settlements, notes, category edits), both of which affect how an agent picks a lookback window.

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?

Two tight sentences with the core behavior front-loaded and the sync use case, including the one-year limit, placed immediately after. The example enumeration is slightly list-y but each item conveys what triggers a feed item.

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 carries the return-value burden; it tells the agent what items appear but not the shape, ordering, or pagination behavior of the feed — notable gaps for a sync tool. The one-year constraint is a helpful addition, but return mechanics remain unspecified.

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 all four parameters are already documented, establishing a baseline of 3. The description only marginally extends changesSince by implying the one-year lookback; it adds nothing about the enum values in `detail` or the account/category defaults.

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 ('Returns feed items created or updated since a timestamp') and scopes it, which separates it from the plain list_transactions/get_transaction siblings by its delta/sync nature. It never names a sibling, so an agent gets the concept but not an explicit disambiguation.

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?

'Useful for syncing' implies the intended context but gives no explicit when-to-use rule, no exclusion of nearby alternatives (list_transactions, list_settled_transactions), and no guidance on choosing it over a plain transaction list.

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