inventory_lot_trace

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

Annotations already declare readOnlyHint=true, and the description reinforces this with 'Reads only, posts nothing.' It adds valuable behavioral context beyond the annotation: the soft found:false response for non-existent lots/serials, the explicit 'never a cross-tenant leak' guarantee, and the scope of the returned history (chronological J02 movements). It does not detail pagination or output shape, but with no output schema and readOnlyHint present, the description carries a reasonable burden and covers the key behavioral traits.

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 description is a single dense paragraph that front-loads the core purpose and then adds the regulatory context, error behavior, and read-only guarantee. Every sentence earns its place, though the regulatory citation (OR 957a) and the cross-tenant leak note add length without directly affecting invocation. It is appropriately sized for a tool with 4 parameters and no output schema.

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?

Given the tool's moderate complexity (two alternative lookup keys, optional disambiguation, required workspaceId, no output schema), the description covers the essential invocation context: what inputs are accepted, what is returned, the soft-failure mode, and the read-only safety profile. It does not specify pagination, sorting, or the exact structure of the movement history, but those are reasonable gaps for a description of this length and are partially covered by the 'full chronological J02 movement history' phrasing.

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 0%, so the description must compensate. It does: it explains that lot_code or serial_number are the primary lookup keys, that item_id optionally disambiguates, and that workspaceId is the required scope. It does not explain the exact format of lot_code/serial_number or whether both can be provided together, but it adds meaning beyond the bare schema property names.

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 states a specific verb ('return'), a specific resource ('current position(s) and full chronological J02 movement history'), and the input keys (lot_code or serial_number, optionally disambiguated by item_id). It also names the regulatory purpose (OR 957a) and explicitly distinguishes itself from a hard error or cross-tenant leak. This clearly differentiates it from siblings like lot_search, serial_get, inventory_movement_history, and stock_on_hand.

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?

The description clearly states when to use it: when you need current position plus full movement history for a lot or serial. It also gives an exclusion: a non-existent lot/serial returns found:false rather than a hard error. However, it does not explicitly name alternative tools for simpler lookups (e.g., lot_get, serial_get, inventory_movement_list) or state when NOT to use it in favor of those, so it misses the explicit when-not/alternatives guidance.

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