Open a shop NPC's sell list in The Mana World after clicking the NPC; pass its ID to retrieve the list.
Open a shop NPC's sell list. Use after clicking a shop NPC (0x00c4 event).
| Name | Required | Description | Default |
|---|---|---|---|
| npc_id | Yes |
Changes observed during successful MCP inspections.
v0.1.4Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It names the trigger event but does not disclose whether this mutates state, what permissions or NPC state are required, whether it is read-only, or what happens to any open shop UI; this is a significant gap for a state-opening action.
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 short sentences, front-loaded with the action and followed by the necessary trigger context. No redundant or filler text.
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 one-parameter opener with no annotations or output schema, the description covers purpose and invocation context but leaves clear gaps in parameter provenance and behavioral effects. It is minimally viable but not fully self-contained.
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% for the single required npc_id parameter. The description only indirectly implies npc_id identifies the clicked shop NPC; it does not explain the parameter's format, how to obtain it from the 0x00c4 event, or what values are valid.
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 and resource: opening a shop NPC's sell list. It is clear what the tool does, but it does not explicitly distinguish this tool from the sibling 'sell' or 'shop_buy' tools, leaving some ambiguity about whether it selects the sell tab or initiates a sale.
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?
It gives a clear precondition: use after clicking a shop NPC (0x00c4 event). This tells the agent when the tool is valid, though it offers no when-not guidance or alternative tools for different shop interaction paths.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.