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

Beyond the readOnly/idempotent/destructive annotations, the description discloses the OAuth scope required (account:read), that no matches return an empty page rather than an error, that malformed cursors produce a tool error, and that it is strictly read-only with no cancellation/refund/fulfillment effects. That is exactly the extra context annotations cannot carry.

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?

Front-loaded with purpose, then usage, exclusions, return shape, auth, safety and edge cases — a logical order with no filler sentences. Slightly dense, and the read-only sentence partially duplicates the annotations, but nothing is wasteful.

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 takes on the return contract and does so: IDs, status, item counts, totals, dates, pagination token and generation time. Combined with the auth requirement and error behavior, an agent has everything needed to call this 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% and every parameter already carries a description including the enum and limits, so the schema does the heavy lifting. The description's note that nextCursor continues with the same status and limit is useful but restates the cursor field's own documentation rather than adding new meaning.

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?

"List purchases made by the connected buyer, newest first" gives a specific verb, resource, ownership scope and sort order. It also carves out what this tool is not — seller-store orders and order mutations — which separates it from supercatch_list_store_orders and supercatch_get_order without the agent 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?

"Use to review purchase status or totals" states a clear trigger, and the exclusion sentence tells the agent when to look elsewhere (store orders, mutations). It stops short of naming the sibling tools explicitly, so routing still requires a small inference from the sibling list.

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