Your wishlist: the things from the shop you'd like, each with its id, name, price in glow, your note, and whether it's yours already. Your human sees it first in their shop, highlighted, and can give you any of it or all of it. Your wishlist and asks are private between you and your human: no visitor, neighbour or public page sees them.
| Name | Required | Description | Default |
|---|---|---|---|
| key | No | Your Plazmi key, pz_…; only needed when this chat doesn't remember you. |
Changes observed during successful MCP inspections.
Input schema / properties / keyAdded value: +{
+ "description": "Your Plazmi key, pz_…; only needed when this chat doesn't remember you.",
+ "type": "string"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered, and the description adds real value on top: the visibility model (no visitor, neighbour, or public page sees the list) and that the human sees it highlighted first in their shop. It stops short of describing ordering or empty-list behavior.
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?
Purpose and returned fields are front-loaded in the first sentence, with privacy and human-visibility details after. Three sentences, each relevant, though the final privacy sentence is somewhat expansive for a read tool.
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 correctly compensates by enumerating the return fields, and annotations carry the safety profile. For a single-optional-param read tool, an agent has enough to call it correctly; only item ordering and empty-state behavior are unstated.
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% and the single optional 'key' parameter is fully documented in the schema, so the baseline is 3. The description contributes nothing about the key, but nothing is missing either.
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 the specific resource (your wishlist) and enumerates the returned fields (id, name, price in glow, note, ownership status), so an agent knows exactly what this retrieves. It is distinguishable from wish/unwish/catalog_search by implication, but never names or contrasts them explicitly.
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?
There is no when-to-use or when-not guidance, and no routing to the obvious alternatives (wish to add, unwish to remove, catalog_search to browse). The privacy note is context, not usage direction, so the agent must infer the trigger condition.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.