mark_seen

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

With no annotations, the description carries the full burden, and it does disclose two important traits: a 1-100 id batch limit and all-or-nothing atomicity when an id is unknown. It omits idempotency/repeat-call behavior, what error surface an unknown id produces, and whether the removal from list_pending is reversible.

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?

One sentence, front-loaded with the action and its effect, then the batching rationale and the failure semantic. No filler; each clause adds an operational fact.

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 one-parameter mutation tool with no annotations and no output schema, the description covers action, effect on a sibling, batching limits, and failure mode. Only the return value and idempotency remain unstated, which is a minor gap at this complexity.

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 0% and the single parameter 'ids' is an untyped-in-prose array of strings, so the description must compensate — and it does, specifying that ids holds 1-100 item ids and that the call is atomic across them. It could go further on whether ids are item ids from list_pending/get_item specifically.

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 ('Mark items as handled') plus the observable effect ('so they leave list_pending'), which lets an agent distinguish it from list_pending without opening either schema. It stops short of naming any other sibling or contrasting with alternatives like prune.

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?

Gives an explicit precondition ('after their facts are saved') and a use case ('a backlog can be marked in a few calls'), which is real when-to-use guidance. It does not state when not to use it, e.g. whether re-marking already-handled items is harmless or whether prune is preferred for old items.

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